Temperate Ecology

The paper presents length analysis, sexual maturity, and degree of stomach fullneu in 201 squid Moroteuthls lngens caught in New Zeiand waters between May and August, 1981. The length-weight relationship was calculated; it equalled W • 0.41 DMt 2 ,23 for males and W c 0.1 DML 2. 7 for females. Relationship between total length and length of statolith core and DML was also calculated, but the correlation values obtained were low (below 0.75). This may indicate that the age of squid Moroteuthlr lngens cannot be determined on the basis of growth rings on statoliths, (D'(\��1<) a conclusion arrived at in earlier paper�.

The effects of climate change and the severe anthropization of local river systems have contributed to the alteration of ecological processes, affecting the water quality in these systems and thus generating conditions for the emergence of algal species. In this context, the object of the present study was to evaluate the potential of remote detection techniques to obtain a spectral characterization of D. geminata under controlled laboratory conditions. This would provide the basic information for the design and implementation of a monitoring and early warning system. D. geminata cells obtained from two southern Chilean river systems were cultivated in the laboratory and analysed using hyperspectral techniques to construct their spectral signatures. The results showed the feasibility of distinguishing between the presence and absence of D. geminata when it occurs in association with other diatom present in the environmental. The results could be the first step towards the design and implementation of a monitoring and early warning system to facilitate existing inspection activities.

The effect of climate change on soil moisture availability has become a significant concern due to its potential to disrupt ecosystems, agricultural productivity, and water resource management. This seminar aims to explore the various aspects of this issue, including the current understanding of climate change, the mechanisms through which it affects soil moisture, and the implications for different sectors. The literature review examines recent studies that have investigated the effect of climate change and soil moisture availability, highlights the key findings, and identifies gaps in knowledge. climate change leads to rising temperatures worldwide. Higher temperatures accelerate evaporation rates, causing more water to evaporate from the Earth's surface, including soil moisture. Warmer temperatures also increase the demand for moisture from the atmosphere, creating a moisture deficit in the soil. This seminar concludes by discussing the importance of climate change effects on soil moisture Availability both Direct and Indirect effects.

Macroalgal beds provide the ecological foundations for most shallow reef ecosystems in temperate environments. With distinctive canopies primarily of brown laminarian algae (northern hemisphere), or laminarian or fucalean algae (southern hemisphere), in many areas these habitats are at risk from human activity. Overexploitation, pollution, and other effects of coastal activities have resulted in significant habitat loss in coastal ecosystems, and human-induced climate change is now seen as a major threat to ecosystem health in marine systems. Understanding the impact of climate change is particularly important for habitat-forming ecosystem engineers like kelps, as these species form the basis of hierarchically organised communities and play a fundamental role in determining community structure and ecological processes. South eastern Australia has experienced increases in marine temperatures at nearly four times the global average, and there is now evidence that, in some locations, m...

Coloration is a trait frequently cited as important to ecological, and thus evolutionary, processes in amphibians. To fully understand the impact of coloration, a consistent method of color measurement is required, which is often achieved by collecting color information in a captive, laboratory setting. However, results from the lab can only be generalized to the field if coloration remains consistent between the two. In this study we collected spectral data from two discrete color morphs of Plethodon cinereus (erythristic and striped) at two distinct time periods while in captivity to determine whether and how their coloration changed over time. We found that brightness in both color morphs decreased similarly through time, though the change was most pronounced in the erythristic morph. Additionally, we examined the overall coloration change over time using multivariate change vectors and found that the magnitude (amount) of multivariate color change was significantly greater in the erythristic morph as compared to the striped morph (for cheek color patches). Intriguingly, the direction of color change in color space was oriented similarly among measured regions within each morph, whereas the direction of color change differed between morphs, indicating that while coloration changed for all individuals, how that change occurred was morph-specific. We propose a physiological mechanism that may be responsible for the observed changes, and suggest several additional mechanisms that may influence labile coloration in these salamanders. Additionally, our findings suggest that quantifying color from individuals held in captivity should be used with caution, as color changes observed in a laboratory setting may not reflect what is seen in the field.

The effects of roads and trails on terrestrial salamanders, primarily plethodontids, can be important. The abundance of terrestrial salamanders often increases with distance from roads. Less is known about the effects of recreational or hiking trails on terrestrial salamanders than is known about the effects of roads. We explored how low and high traffic trails in a suburban biological reserve affect the relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus). We found more salamanders under cover objects next to low traffic trails compared to either high traffic trails or wooded areas without trails. At wooded sites, we found only striped morphs whereas at high traffic sites we found only unstriped morphs. Low traffic sites included a range of color morph frequencies. The proportion of females found in each site did not differ, nor did the mean size of the salamanders. Our results suggest that the impact of recreational walking trails needs to be examined more closely to see how and why the distributions of P. cinereus, and potentially other woodland salamanders, are affected and what trail characteristics are important in driving the apparent effects. Such information will contribute to the design and maintenance of walking trails in natural areas that minimize effects on terrestrial salamanders, and likely other organisms.

Didymosphenia geminata is a stalk-forming diatom capable of creating thick benthic mats in low-nutrient streams. There are two hypotheses to explain the rapid worldwide increase in occurrence of nuisance D. geminata mats: (a) Cells are spread among rivers and across broad ecoregions through natural and anthropogenic vectors, or (2) pre-existing D. geminata populations are forming mats in response to changing environmental conditions within the habitat. Low phosphorus (P) concentrations are a major trigger for stalk production by D. geminata cells. Although the environmental change hypothesis is gaining support among researchers, long-term data sets demonstrating declining P concentrations prior to reported mat formation have been essentially absent from the literature. Here, we present long-term datasets for two case studies for which long-term P and D. geminata data coincide: the Matapedia River in Eastern Canada and the Kootenai River below Libby Dam in Montana, United States. Both rivers had declining P levels over time. However, there was a 2-and 20-year lag time, respectively, between mat development and reaching the previously proposed average 2 μg/L soluble reactive P threshold for development. Although the Matapedia River provides some support of the environmental change hypothesis, the Kootenai River data set suggests other environmental factors may play a role in mat development. The data presented do not rule out the environmental change hypothesis but do suggest there may be conditions in addition to low P that must be met for mats to form and the environmental change hypothesis can likely be refined to include more parameters to better understand and mitigate the influence of mats.

Didymosphenia geminata is a species of freshwater diatom that is known as invasive and is propagating quickly around the world. While invasive species are generally considered a nuisance, this paper attempts to find useful applications for D. geminata in the biomedical field and wastewater remediation. Here, we highlight the polysaccharide-based stalks of D. geminata that enable versatile potential applications and uses as a biopolymer, in drug delivery and wound healing, and as biocompatible scaffolding in cell adhesion and proliferation. Furthermore, this review focuses on how the polysaccharide nature of stalks and their metal-adsorption capacity allows them to have excellent wastewater remediation potential. This work also aims to assess the economic impact of D. geminata, as an invasive species, on its immediate environment. Potential government measures and legislation are recommended to prevent the spread of D. geminata, emphasizing the importance of education and collaborati...

Hickerson, 2014). As a result, color morphs are often inferred to reflect differences in mating tactics (Hurtado-Gonzales & Uy, 2009), with their maintenance driven in part by sexual selection (Calsbeek & Cox, 2010; Lande, 1981). In particular, nonrandom mating has the potential to contribute to the evolution and maintenance of phenotypic diversity within a population and is likewise regarded as an

Numerous authors have studied the diet of the Eastern Red-backed Salamander (Plethodon cinereus) and have described this species as a generalist predator of invertebrates. In most studies, prey taxa are identified to the family or order level. Additionally, few studies have directly assessed dietary preference by comparing diet to available prey. We chose an important component of the diet of red-backed salamanders (ants) to test whether salamanders altered their diets temporally and to determine if salamanders preyed on a subset of available ant prey. We identified ant species in salamander diets over a 13 mo period. In the fall season we also compared ants in stomach contents to those available in the surrounding leaf litter to determine if territorial residents of P. cinereus selectively forage on different ant species. We found significant temporal differences in ant species incorporated in the diet of P. cinereus that were consistent with our detailed examination of salamander ant preference in the fall. Our estimates of prey diversity and richness indicate that salamanders consumed a subset of available ant species. Aphaenogaster picea, an abundant species that prefers similar microhabitat characteristics to P. cinereus, made up a majority of the ants in the diet. However, our results indicate that P. cinereus avoids foraging on Myrmica punctiventris, Myrmecina americana, and Lasius alienus, ants that are among the most abundant species in the forested areas of northeastern Ohio where the study was conducted. These species are potentially aggressive and/or chemically defended, reducing their profitability as prey. The striped and unstriped morphs of red-backed salamanders foraged similarly on ant taxa, but the striped morph consumed significantly more ants and was found within territories that contained more ants. Our findings suggest selective foraging may be more common among generalist predators than previously considered, and we propose striped and unstriped morphs may represent a trophic polymorphism in P. cinereus.

The reproductive pattern of L.&go vulgaris and L&go forbesi was studied on the basis of gonad maturation, mating and spawning in males and females of both species which were present off the northwest coast of Spain (Galicia), between February 1991 and February 1993. The mature females of both species have several modes of egg sizes and developmental stages within the ovary. Several signs indicate that both female L.&go vulgaris and L. forbesi undergo partial ovulation at the time of spawning, the spawning period being relatively long, although in no case representing the greatest fraction of the animal's life before death. Egg-laying occurring in separate batches and somatic growth between egg batchs has not been observed. This reproductive pattern is defined as intermittent terminal spawning. Some other terms describing different cephalopod reproductive strategies are also defined.

Squids typically demonstrate considerable plasticity in individual growth rates. However, it is not known if individuals growing at different rates also differ at lower levels of organisation. We wished to determine if Seploteuthis lessoniana individuals that were larger than predicted for their age dlffered in their digestive gland and mantle muscle tissue proximal composition or mantle muscle structure, compared with individuals that were smaller for their age than predicted. The residual, the difference between the observed size-at-age and that predicted by the growth equation, was used as a measure of the difference in an individual's lifetime growth from the population average. Individual squid varied considerably in their size-at-age, with juveniles showing less variation than adults. Juverules had greater concentrations of lipid in their muscle tissue, perhaps due to an emphasis on storing energy reserves in this critical period of thelr life. Differences in biochemical constituents in both the digestive gland and muscle tissue were not related to the size-at-age of individuals, despite biochemical make-up being the lowest organisational level of growth. This may be due to whole animal growth and changes in biochemical composition occurring on different time scales. There was no relationship between the size-at-age of individuals and average mantle muscle fibre size. A strong relationship, however, existed between the size of mantle muscle blocks and the size-at-age of individuals for both juvenile and adult individuals, suggesting that larger muscle blocks are related to both body size and faster individual growth rates. This study demonstrates a clear relationship between mantle muscle structure and growth and the size-at-age of S. lessoniana individuals. KEY WORDS: Squid. Size-at-age. Condition. Muscle tissue. Digestive gland O Inter-Research 2000 Resale of fuU article not permitted

Background: Co-occurrence of distinct colour forms is a classic paradox in evolutionary ecology because both selection and drift tend to remove variation from populations. Apostatic selection, the primary hypothesis for maintenance of colour polymorphism in cryptic animals, proposes that visual predators focus on common forms of prey, resulting in higher survival of rare forms. Empirical tests of this frequency-dependent foraging hypothesis are rare, and the link between predator behaviour and maintenance of variation in prey has been difficult to confirm. Here, we show that predatory birds can act as agents of frequency-dependent selection on terrestrial salamanders. Polymorphism for presence/absence of a dorsal stripe is widespread in many salamander species and its maintenance is a long-standing mystery. Results: We used realistic food-bearing model salamanders to test whether selection by wild birds maintains a stripe/no-stripe polymorphism. In experimental manipulations, whichever form was most common was most likely to be attacked by ground-foraging birds, resulting in a survival advantage for the rare form. Conclusion: This experiment demonstrates that frequency-dependent foraging by wild birds can maintain colour polymorphism in cryptic prey.

Didymosphenia geminata is a stalk-forming diatom capable of creating thick benthic mats in low-nutrient streams. There are two hypotheses to explain the rapid worldwide increase in occurrence of nuisance D. geminata mats: (a) Cells are spread among rivers and across broad ecoregions through natural and anthropogenic vectors, or (2) pre-existing D. geminata populations are forming mats in response to changing environmental conditions within the habitat. Low phosphorus (P) concentrations are a major trigger for stalk production by D. geminata cells. Although the environmental change hypothesis is gaining support among researchers, long-term data sets demonstrating declining P concentrations prior to reported mat formation have been essentially absent from the literature. Here, we present long-term datasets for two case studies for which long-term P and D. geminata data coincide: the Matapedia River in Eastern Canada and the Kootenai River below Libby Dam in Montana, United States. Both rivers had declining P levels over time. However, there was a 2-and 20-year lag time, respectively, between mat development and reaching the previously proposed average 2 μg/L soluble reactive P threshold for development. Although the Matapedia River provides some support of the environmental change hypothesis, the Kootenai River data set suggests other environmental factors may play a role in mat development. The data presented do not rule out the environmental change hypothesis but do suggest there may be conditions in addition to low P that must be met for mats to form and the environmental change hypothesis can likely be refined to include more parameters to better understand and mitigate the influence of mats.

The emerging amphibian disease chytridiomycosis, which is caused by the fungal pathogen (Batrachochytrium dendrobatidis, Bd), has caused mass mortalities of native amphibian populations globally. There have been no previous studies on the relationships between stress hormones in free-living amphibians and Bd infections. In this study, we measured urinary corticosterone metabolite concentrations and Bd infections within free-living populations of male Stony Creek frog (Litoria wilcoxii) in Queensland, Australia. Prevalence of Bd zoospores from frog skin swabs was quantified using a real-time quantitative PCR technique. A urinary corticosterone enzyme-immunoassay (EIA) was validated using adrenocorticotropic hormone (ACTH) challenge. Urinary corticosterone concentrations of male frogs increased within 1-2 days after ACTH challenge and returned to baseline levels within 3 days post-ACTH injection. None of the frogs showed any rise in urinary corticosterone after saline injections. Individual male frogs showed either low or high baseline corticosterone concentrations. Male frogs identified as positive for Bd infection had significantly higher baseline urinary corticosterone concentrations in comparison to Bd negative male frogs. Urinary corticosterone EIA provides a reliable indication of stress in this frog species and this non-invasive physiological tool can be used to further assess the dynamics of Bd infections and physiological stress responses in other native amphibians.

Background Ecological functions and processes in urban ecosystems are governed by various human activities. City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments. A trait of high importance, the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons (Columba livia) in North African urban habitats. Methods Different body morphometrics, hematological and hemoparasitic parameters were quantified on free-living Feral Pigeons in urban environments of northern Algeria. Moreover, plumage melanin-based coloration (MBC) was measured and the data collected at the individual scale was correlated with the previous parameters using linear an...

Behavioural and Evolutionary Ecology, Faculte des Sciences, CP 160/12, Universite Libre de Bruxelles, Avenue F.D. Roosevelt 50, B-1050 Brussels, Belgium, yroisin@ulb.ac.be, thomas.bourguignon@ulb.ac.be LAPSCO, UMR-CNRS 6024, Universite Blaise Pascal, 34 avenue Carnot, F-63037 ClermontFerrand cedex, France, corbara@univ-bpclermont.fr CNRS-Guyane (UPS 2561 and UMR-CNRS 5174), 16 avenue Andre Aron, F-97300 Cayenne, France, alain.dejean@wanadoo.fr Laboratoire d&#39;Evolution et Diversite Biologique, UMR-CNRS 5174, Bât. 4R3, Universite Toulouse III, 118 route de Narbonne, F-31062 Toulouse cedex 4, France, orivel@cict.fr Section of Biological Evaluation, Royal Belgian Institute of Natural Sciences, Rue Vautier 29, B-1000 Brussels, Belgium, Maurice.Leponce@naturalsciences.be

In this paper we report information about the sexual maturity process of 245 Octopus vulgaris specimens (75 females and 170 males) from the Mediterranean Sea. For both sexes, six stages of sexual maturity (immature, developing, maturing, mature, spawning, and spent) are identified on the basis of macroscopic and microscopic observations of the reproductive system and linked with some reproductive indices. A good correspondence between gonad appearance and its histological structure is observed, highlighting, in females, how oviducal gland morphology plays a crucial role in the macroscopic evaluation of maturity. The Gonadosomatic and Hayashi indices, in the two genders, and the Oviducal Gland index in females alone do not allow distinguishing all the stages in an irrefutable way. Data on the potential fecundity, oocyte and spermatophore size are reported and compared with literature. In addition, spermatophore components are also computed. The results reported in this paper lead to ...

Background: Co-occurrence of distinct colour forms is a classic paradox in evolutionary ecology because both selection and drift tend to remove variation from populations. Apostatic selection, the primary hypothesis for maintenance of colour polymorphism in cryptic animals, proposes that visual predators focus on common forms of prey, resulting in higher survival of rare forms. Empirical tests of this frequency-dependent foraging hypothesis are rare, and the link between predator behaviour and maintenance of variation in prey has been difficult to confirm. Here, we show that predatory birds can act as agents of frequency-dependent selection on terrestrial salamanders. Polymorphism for presence/absence of a dorsal stripe is widespread in many salamander species and its maintenance is a long-standing mystery. Results: We used realistic food-bearing model salamanders to test whether selection by wild birds maintains a stripe/no-stripe polymorphism. In experimental manipulations, whichever form was most common was most likely to be attacked by ground-foraging birds, resulting in a survival advantage for the rare form. Conclusion: This experiment demonstrates that frequency-dependent foraging by wild birds can maintain colour polymorphism in cryptic prey.

A major diculty confronting the determination of cephalopod reproductive life history is assessing over what portion of the life span an individual is reproductively mature and actively depositing eggs. This paper assesses the potential of the tropical Sepioteuthis lessoniana and two genetic types of the temperate Sepioteuthis australis, to spawn multiple batches of eggs at discrete times throughout the adult life span. This is achieved by histological examination of the ovarian gametogenic cycle and detailed morphological assessments of the reproductive system, in conjunction with other biological information. The genetic type of S. australis found at the northern limits of its Australian distribution showed evidence of a high correlation between body size and quantity of mature eggs, suggesting that eggs may be accumulating to be laid in a single batch. Although maturation was also a sizerelated process in S. lessoniana and Tasmanian S. australis, oviduct size was not correlated with body weight in mature females, which is indicative of multiple spawning. Further supporting evidence includes relatively low gonadosomatic indices, the heavier weight of the ovary relative to the oviduct, and the feeding activity of mature animals. Mature S. lessoniana and S. australis individuals were present at each location over very wide age and size ranges. In Tasmanian waters, there were distinct seasonal dierences in the reproductive biology of S. australis. Summer-caught individuals had much higher gonadosomatic indices and may have been laying larger batches of eggs compared with winter-caught individuals. Summer-caught females also showed a negative correlation between egg size and egg number within the oviduct, suggesting that some individuals were producing fewer, larger eggs and others many smaller eggs. Evidence suggests that considerable¯exibility is inherent in the reproductive strategy of both S. lessoniana and S. australis.

This study aimed at showing the applicability of using a combination of four sampling methods (i.e., Winkler extractors, pitfall traps, baiting and manual collection), something most often conducted in the tropics, to create an inventory of ant species diversity in temperate environments. We recorded a total of 33 ant species in the Grands Causses by comparing three vegetal formations: a steppic lawn ('causse' sensu stricto), which was the most species-rich (29 species), followed by an oak grove (22 species) and a pine forest (17 species). No sampling method alone is efficient enough to provide an adequate sampling, but their combination permits one to make a suitable inventory of the myrmecofauna and to obtain information on the ecology of these ant species. To cite this article: S.

Ant fauna as ecological indicator in Italian agroecosystems. Ants can be informative ecological indicators also in ecosystems where the human impact can limit the number of available indicators, as in the agro-ecosystems. Ants are a very important component of several ecosystems because they can be dominant in term of biomass and abundance and they can act as ecological engineers, keystone species or, negatively, as invasive species. Moreover, their ecology is well studied, mainly in term of modification of ant community structure due to factors as stress, disturbance and behavioural dominance. Finally, their sampling is relative low cost and low time consuming. For all these reasons, ants are included in environmental monitoring programs in many regions as the Australian continent or North America. However, the use of these insects as ecological indicators is poorly widespread in the Palaearctic area. The aim of this research was to verify the value of ants as ecological indicators in Italian agro-ecosystems. Sampling areas were selected inside the Regional Fluvial Park of Taro River (Parma, Northern Italy). In particular, the ant community structure was studied and compared between cultivation practices for the production of fodder for dairy cow involved in the production of Parmigiano-Reggiano cheese: lucerne monocultures and permanent grasslands. Data from pitfall sampling were analysed through the Indicator Species Analysis. The interpretation of results using the Functional Group approach shows that the different human impact associated with the two cultures affects the composition of ant community structure. In conclusion, this preliminary research suggests that ants can be useful indicators of environmental quality also in Italian agro-ecosystems.

Amphibians are declining worldwide. Recently an alarmingly steep decline in abundances of Fire Salamanders was reported in the Netherlands. In 2013 a unique fungus, Batrachochytrium salamandrivorans, was isolated and shown to be responsible for the observed mortality in the Fire Salamander populations. In a project funded by the relevant Austrian ministry, we are cooperating with schools to study the distribution and encourage the protection of Alpine and Fire Salamanders. Consequently we decided to test some of the Fire Salamander populations around Salzburg for the presence of B. salamandrivorans within the framework of this project. In addition, we involved the school children in collecting samples in order to introduce them to a current topic and to sensitize them to issues of amphibian protection. Of the 58 skin samples of Fire Salamanders from 8 different locations collected in autumn 2013, none tested positive for the presence of B. salamandrivorans. These results suggest that there is no evidence for infected Fire Salamanders in the study areas around Salzburg.

The effects of roads and trails on terrestrial salamanders, primarily plethodontids, can be important. The abundance of terrestrial salamanders often increases with distance from roads. Less is known about the effects of recreational or hiking trails on terrestrial salamanders than is known about the effects of roads. We explored how low and high traffic trails in a suburban biological reserve affect the relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus). We found more salamanders under cover objects next to low traffic trails compared to either high traffic trails or wooded areas without trails. At wooded sites, we found only striped morphs whereas at high traffic sites we found only unstriped morphs. Low traffic sites included a range of color morph frequencies. The proportion of females found in each site did not differ, nor did the mean size of the salamanders. Our results suggest that the impact of recreational walking trails needs to be examined more clo...

Juvenile squids were grown in individual 2.6-l oating enclosures and were fed either a high-or a lowration diet of ®sh and the crustacean Acetes. Squids were maintained for a maximum of 44 days in two experiments. The high-ration individuals reached a signi®cantly larger size in both experiments (27, 25.5 mm mean mantle length, ML) compared to their low-ration siblings (19 mm mean ML) in both experiments. The statolith increment widths prior to the start of the experiment were signi®cantly wider (between 3 and 4 lm) compared to the increment widths after the start of the experiment (between 2 and 3 lm) both for the low-and the high-ration squids. High-ration squids also had sig-ni®cantly wider increments and larger statoliths than their low-ration siblings. Even though we detected consistent trends in daily statolith increment widths for the dierent feeding regimes, we could not detect variation in increment widths at a daily level of resolution (i.e. as a result of dierences in day-today food intake at an individual level). This was probably due to the relatively consistent diet experienced by each individual. These experiments revealed that ration level in¯uences squid growth rate, statolith size and daily statolith increment width.

Aspects of growth and reproduction of the bigfin reef squid Sepioteuthis lessoniana (Lesson, 1830) in the coastal waters of Zanzibar were investigated with a view to obtaining basic information that could be used in the management of the squid fishery in the area. A total of 664 specimens, comprising 344 females and 320 males, were collected between April 1994 and March 1995. The size of individuals ranged from 63mm to 347mm and 72mm to 277mm dorsal mantle length (DML) for males and females respectively. Growth was not significantly different (p>0.001) between males and females as revealed by length (L)-weight (W) relationship, thus the following expression was used to describe the growth of S. lessoniana: W=0.0005 L 2.255. Both males and females exhibited allometric growth. Gonad maturation, as revealed by maturity stages and indices, peaked in July, indicating that the spawning period begins around July. Size at maturity was determined by statistical and graphical methods. Size (DML ± 95% CL) at maturity as determined by the statistical method was 138.9 ± 6.4mm and 162 ± 4.3mm for males and females respectively, while the graphical method yielded 149.5mm for males and 162.8mm for females. Fecundity for female individuals ranged from 180 to 1180 eggs with a mean of 680 eggs for individuals of size range 140-249mm DML.

The validity of a semi-automatic image analysis system employing digital image enhancement was demonstrated by re-analysing a set of previously analysed, knownage, Sepioteuthis lessoniana statoliths. Linear regression models using both the manual and semi-automatic growth increment counts successfully predicted the true age of the test statoliths to a high degree of accuracy and precision and fully supported the one increment per day hypothesis. Thus this set of known age statoliths served as a reference standard for the counting method. After ''calibrating'' the semi-automatic image analysis system with the reference standards the method was then used to determine the ages of a large (n=312) set of Illex coindetii statoliths of unknown age. The results of this analysis were less clear than the S. lessoniana analysis. The semi-automatic counts predicted mantle lengths (ML) more precisely than did the manual counts. Significant differences were found between the two counting methods. For the Illex data set, the linear model to estimate ML from putative age predicted negative y-intercept values for both sexes and counting methods. Thus a power function model was selected as the more biologically meaningful predictor of ML. The accuracy of the I. coindetii analysis cannot be determined as the daily increment hypothesis remains to be verified for this species.

There are just a few records of giant squid of the species Architeuthis captured alive. Two living sub-adult females of Architeuthis of 180 and 135 cm mantle length with total weights of 148 and 81kg respectively, were caught 34 miles o¡shore in northern Spanish Atlantic waters (43852.54 0 N^05818.74 0 W) in December 1999 and January 2001. From April 1999 to January 2000 in the same area, another giant squid of 102 kg as well as a single tentacle measuring 5 m, and another tentacle of 2 m long were caught. Another ¢ve living specimens were captured and 11 more animals were caught dead during the last 15 years in the same area.

The effects of roads and trails on terrestrial salamanders, primarily plethodontids, can be important. The abundance of terrestrial salamanders often increases with distance from roads. Less is known about the effects of recreational or hiking trails on terrestrial salamanders than is known about the effects of roads. We explored how low and high traffic trails in a suburban biological reserve affect the relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus). We found more salamanders under cover objects next to low traffic trails compared to either high traffic trails or wooded areas without trails. At wooded sites, we found only striped morphs whereas at high traffic sites we found only unstriped morphs. Low traffic sites included a range of color morph frequencies. The proportion of females found in each site did not differ, nor did the mean size of the salamanders. Our results suggest that the impact of recreational walking trails needs to be examined more clo...

Soil physics deals with the dynamics of physical soil components and their phases as solid, liquids, and gases. It draws on the principles of physics, physical chemistry, engineering, and meteorology. It is especially important in this day and age because most farmers require an understanding of agro ecosystems. Nowadays, soil is increasingly under pressure as a limited resource for the production of food, energy and raw materials. In more recent years this list has grown to include anthropologists, economists, engineers, medical professionals, military professionals, sociologists, and even artists. The central importance of soil for the functioning of terrestrial systems is increasingly recognized. Critically relevant for water quality, climate control, nutrient cycling and biodiversity, soil provides more functions than just the basis for agricultural production. This has led to an increasing demand for concepts assessing soil functions so that they can be adequately considered in decision-making aimed at sustainable soil management. The various soil science disciplines have progressively developed highly sophisticated methods to explore the multitude of physical, chemical and biological processes in soil. This approach has been strengthened and reinforced as current research continues to use experts trained in both soil science and related fields and by the wide array of issues impacting the world that require an in-depth understanding of soils. Of fundamental importance amongst these issues are biodiversity, bio-fuels/energy security, climate change, ecosystem services, food security, human health, land degradation, and water security, each representing a critical challenge for Research. The focus of soil physics research and that of soil science in general, has gradually broadened from mostly agricultural production issues to more comprehensive studies of Sub-surface water flow and chemical transport geared toward environmental issues.

My study aimed to assist land managers and conservation plans to manage temperate butterfly diversity in anthropogenic habitats. Simple correlations from past studies found both positive and no relationships between plant richness and butterfly richness at multiple scales. In contrast, many studies have also shown co-existing species partition resources, and species richness increases with resource abundance. It has been suggested that plant richness and butterfly richness correlations may be due to both organisms responding to resource abundance. Furthermore, invasive species disrupt food webs and present problems for land management. To elucidate possible disruptions by a local invasive plant, Galium verum, inflorescence abundances of Galium spp. were analyzed as a distinct predictor variable from total non-Galium genera inflorescence abundance.

The emerging amphibian disease chytridiomycosis, which is caused by the fungal pathogen (Batrachochytrium dendrobatidis, Bd), has caused mass mortalities of native amphibian populations globally. There have been no previous studies on the relationships between stress hormones in free-living amphibians and Bd infections. In this study, we measured urinary corticosterone metabolite concentrations and Bd infections within free-living populations of male Stony Creek frog (Litoria wilcoxii) in Queensland, Australia. Prevalence of Bd zoospores from frog skin swabs was quantified using a real-time quantitative PCR technique. A urinary corticosterone enzyme-immunoassay (EIA) was validated using adrenocorticotropic hormone (ACTH) challenge. Urinary corticosterone concentrations of male frogs increased within 1-2 days after ACTH challenge and returned to baseline levels within 3 days post-ACTH injection. None of the frogs showed any rise in urinary corticosterone after saline injections. Individual male frogs showed either low or high baseline corticosterone concentrations. Male frogs identified as positive for Bd infection had significantly higher baseline urinary corticosterone concentrations in comparison to Bd negative male frogs. Urinary corticosterone EIA provides a reliable indication of stress in this frog species and this non-invasive physiological tool can be used to further assess the dynamics of Bd infections and physiological stress responses in other native amphibians.

Widespread population declines in terrestrial Plethodon salamanders occurred by the 1980s throughout the Appalachian Mountains, the center of global salamander diversity, with no evident recovery. We tested the hypothesis that the historic introduction and spread of the pathogenic fungus Batrachochytrium dendrobatidis (Bd) into the eastern US was followed by Plethodon population declines. We expected to detect elevated prevalence of Bd prior to population declines as observed for Central American plethodontids. We tested 1,498 Plethodon salamanders of 12 species (892 museum specimens, 606 wild individuals) for the presence of Bd, and tested 94 of those for Batrachochytrium salamandrivorans (Bs) and for ranavirus. Field samples were collected in 2011 from 48 field sites across a 767 km transect. Historic samples from museum specimens were collected at five sites with the greatest number and longest duration of collection (1957-987), four of which were sampled in the field in 2011. No...

Widespread population declines in terrestrial Plethodon salamanders occurred by the 1980s throughout the Appalachian Mountains, the center of global salamander diversity, with no evident recovery. We tested the hypothesis that the historic introduction and spread of the pathogenic fungus Batrachochytrium dendrobatidis (Bd) into the eastern US was followed by Plethodon population declines. We expected to detect elevated prevalence of Bd prior to population declines as observed for Central American plethodontids. We tested 1,498 Plethodon salamanders of 12 species (892 museum specimens, 606 wild individuals) for the presence of Bd, and tested 94 of those for Batrachochytrium salamandrivorans (Bs) and for ranavirus. Field samples were collected in 2011 from 48 field sites across a 767 km transect. Historic samples from museum specimens were collected at five sites with the greatest number and longest duration of collection (1957-987), four of which were sampled in the field in 2011. No...

Amphibian declines have been documented worldwide. Chytridiomycosis, a disease caused by the aquatic fungus Batrachochytrium dendrobatidis (Bd), is one of the causes associated with these declines. Occurrence, rate of infection and mortality due to chytridiomycosis in amphibians depend on multiple factors including habitat and life-style (aquatic/terrestrial). Bd infection is lower in terrestrial than in aquatic species, but a fully terrestrial life-style alone may not explain the absence of Bd in some species. Low individual dispersal, decreasing the occurrence of contact with infected organisms, could also favour lower Bd infection. To survey the occurrence of Bd infection in fully terrestrial salamanders with low dispersal, we sampled the Sardinian Hydromantes species to measure their level of infection. Bd was not detected and likely absent in Sardinian Hydromantes. This phenomenon could be explained by a combination of terrestrial habitat, low dispersal, and occurrence mostly in habitats where other amphibians do not occur. "il fontaniere" of Tertenia for their help with the sampling. Linda Harant and Karin Fischer helped with the laboratory work. We are grateful to Stefan Lötters, Benedikt Schmidt, and two anonymous reviewers for their comments on this article. We are thankful to the Ministero dell'Ambiente, della Tutela del Territorio e del Mare for issuing the collecting permit 9333 (03/04/2007). YC and AvdM were financially supported by FCT, Fundação para a Ciência e Tecnologia (Portugal), postdoctoral fellowships SFRH/BDP/73515/2010 and SFRH/BDP/48042/2008, respectively.

We compared the ability of 33 plant species collected in forest to have their seeds dispersed by the wood red ant Myrmica ruginodis. The elaiosome-bearing seeds (species Chelidonium majus, Colchicum autumnale, Luzula forsteri, Viola reichenbachiana, Luzula multiflora, Melica uniflora) and the small and light caryopses of the grasses (Holcus mollis, Agrostis capillaris, Deschampsia flexuosa, Poa trivialis, Holcus lanatus) are the most efficiently collected by ants. The seed quantity removed by ants is correlated negatively with their length. No significant correlation is found between the rate of seed removal and the frequency of the plants in the field at the scale of the study.

The multi-species ant assemblages were studied in the Crimea Mountains, in 9 types of plant associations in the plateau pastures as well as on the southern and northern slopes of the Main Range. A list of 18 ant species with data on their distribution in biotopes and also layers and the structure of their foraging territories is given. The hierarchical organization of multi-species ant assemblages and different strategies of nest location of the influents depending on the dominant species and its territoriality were investigated. Territoriality of each dominant species was determined by the frequency of foraging areas without nests of other species. Depending on dominant territoriality and the number of dominant species, the following classification of multi-species assemblages is proposed. (1) Monodominant assemblages with weakly expressed territoriality of the dominant species. Low density of the workers of Camponotus aethiops in the foraging territory determines weak interactions with influent species. The settling pattern of the influents shows no evident dependence on the dominant. Weakly expressed territoriality of the dominant allows non-territorial species to exist on the dominant's territory. Such species were not found in other types of ant assemblages. (2) Monodominant assemblages with strongly expressed territoriality of the dominant species. The settling pattern of the influents shows the subordinate species to avoid those of higher ranks in the hierarchy, thus decreasing the probability of conflicts. The influents settle in the neutral zones as well as in the foraging territory of the dominant, so as to reduce competition with the subdominant species Formica cunicularia. Such a strategy reduces the probability of interspecific conflicts in biotopes with fewer vegetation layers than in the forests. (3) Bidominant assemblages with a variable dendrobiont dominant are typical among forest assemblages. Coexistence of two dominant species is possible when foraging of one of them is completely or partly restricted to one vegetation layer. The subdominant species avoid settling in the foraging territory of the dominant that occupies the same layer. When the dendrobiont dominant Crematogaster schmidti drops out of the assemblage, it (and its role in the assemblage) is replaced by other dendrobiont species Lasius emarginatus which otherwise acts as the 1st order subdominant in C. schmidti assemblages. (4) Polydominant assemblages are characterized by the presence of as many as 3 dominant species, namely Crematogaster schmidti, Camponotus aethiops, and Plagiolepis tauricus. The coexistence of the dominants is possible due to use of different layers (one species is a dendrobiont, the other two are herpeto-hortobionts), different activity periods (round-the-clock in Crematogaster schmidti, night in Camponotus aethiops, and daytime in P. tauricus), and different size classes of the workers (3rd, 5th, and 1st, respectively). The different size classes of workers reduce competition for food. Thus, when the number of dominant species in the assemblage increases, so does the number of mechanisms facilitating their coexistence.

Predators have to deal with the problem of prey shifting during predator's ontogenesis. The ontogenetic shift in the prey capture of prey-specialized species should be associated with a change in their predatory traits. Here, we focused on the ant-eating Zodarion rubidum, a spider strictly specialized on ants. It uses potent venom to immobilize prey. We tested whether there is a change during the ontogenesis of the spider species in traits related to capture efficiency. We kept spiders from the juvenile to adult stage on a monotypic diet composed of one of four ant species, small and large ant species from two subfamilies. We tested the capture efficiency of all spiders at the beginning and at the end of the experiment after being reared on a certain ant species, and then we swapped the spiders and tested them with the other ant species. For each trial, we measured the number of attacks (bites) and the paralysis latency. Afterwards venom glands were extracted and analysed using MALDI-TOF mass spectrometry and 1D-SDS-PAGE gel electrophoresis. We found that spiders on all diets improved their capture efficiency during ontogenetic development. We hypothesize that the improvement was due to an increase in the amount of venom injected. Thus, we did not find an ontogenetic shift in the predatory traits. Nor was there a significant difference in the composition of low and high molecular weight venom compounds among diet groups, suggesting that the consumption of a prey has little effect on venom composition.

monthly samples of L. vulgaris were collected from this commercial trawl ¢shery. The maturation pattern for males and females was described from the proportion of immature, maturing and mature animals in the samples and using a maturation index. A range of reproductive indices derived from the morphometrics of the somatic and reproductive systems were also estimated to provide comparative information. The proportion and an abundance index of mature and immature animals in commercial landings in the period 1983^1994 were calculated to provide comparative results of maturity and recruitment respectively. Peaks of mature animals were mainly seen between November and January. The summer months exhibited the maximum recruit abundance. Age determinations were also undertaken in order to obtain the hatching peaks and to complete the proposed life cycle of L. vulgaris on the Saharan Bank. A main hatching peak was observed in spring, particularly in May. The age^size relationship suggests di¡erences related to sex and possibly to hatching season. The wide range of size at maturity observed in male L. vulgaris is analysed and discussed. Males showed a seasonal pattern in size at maturity. The dorsal mantle length^body weight relationship and the sex ratio were determined. The sex ratio exhibits a seasonal pattern in relation to body size. Results are compared with information on this species from European waters.

Numerous authors have studied the diet of the Eastern Red-backed Salamander (Plethodon cinereus) and have described this species as a generalist predator of invertebrates. In most studies, prey taxa are identified to the family or order level. Additionally, few studies have directly assessed dietary preference by comparing diet to available prey. We chose an important component of the diet of red-backed salamanders (ants) to test whether salamanders altered their diets temporally and to determine if salamanders preyed on a subset of available ant prey. We identified ant species in salamander diets over a 13 mo period. In the fall season we also compared ants in stomach contents to those available in the surrounding leaf litter to determine if territorial residents of P. cinereus selectively forage on different ant species. We found significant temporal differences in ant species incorporated in the diet of P. cinereus that were consistent with our detailed examination of salamander ant preference in the fall. Our estimates of prey diversity and richness indicate that salamanders consumed a subset of available ant species. Aphaenogaster picea, an abundant species that prefers similar microhabitat characteristics to P. cinereus, made up a majority of the ants in the diet. However, our results indicate that P. cinereus avoids foraging on Myrmica punctiventris, Myrmecina americana, and Lasius alienus, ants that are among the most abundant species in the forested areas of northeastern Ohio where the study was conducted. These species are potentially aggressive and/or chemically defended, reducing their profitability as prey. The striped and unstriped morphs of red-backed salamanders foraged similarly on ant taxa, but the striped morph consumed significantly more ants and was found within territories that contained more ants. Our findings suggest selective foraging may be more common among generalist predators than previously considered, and we propose striped and unstriped morphs may represent a trophic polymorphism in P. cinereus.

The standardized 'Ants of the Leaf Litter' protocol aims to facilitate the use of ground-foraging and litter-dwelling ants in biodiversity assessment and monitoring programs. It was initially developed to characterize assemblages from tropical rain forests and is based on two main techniques: Winkler extractions and pitfall traps. Here, we tested to what extent this protocol was adapted to tropical dry forests and affected by the rainfall regime. Our 10 study sites were located along an aridity gradient (average annual rainfall: 350-1300mm) in the Gran Chaco. The number of species collected per sampling effort increased with aridity for pitfalls but followed an opposite trend for Winkler samples. This trend could be explained by the low daytime foraging activity in the leaf litter during drought periods. In arid and semiarid regions the good performance of pitfalls was probably related to their 24-h operation and to the attractiveness of the water they contained. Our results stress that the Winkler method used in the Ants of the Leaf Litter protocol may not be cost-effective during periods of drought and may lead to severe underestimations of litter ant diversity in tropical dry forests.

Age and size-at-maturity of Loligo vulgaris from Portuguese waters were evaluated in order to explain its complex population structure, which is strongly influenced by continuous spawning. Age was obtained by increment counting in statoliths. Maturity ogives by age group indicated that males mature one month earlier (at 277 days) than females (at 298 days). Females mature at a ML 50% of 17.6 cm, while males mature at smaller sizes. The later, however, showed a high degree of complexity in the size at maturity with evidence of two size at maturity groups. In both sexes, maturity was ultimately found to be primarily dependent on size rather than age. The effect of hatching season on age-at-maturity, size-at-maturity and reproductive investment was analysed by comparing two groups of squid hatched under distinct environmental conditions, namely the temperature during the first 3 months of life, the cold cohort (CC), hatching between December and March and the warm cohort (WC), hatching between May and September. Significant differences were found between cohorts on age-at-maturity, size-at-maturity and reproductive investment, giving indication of the environmental influences on sexual maturity. CC squid mature ca. 2 months later in life than WC squid and at a significantly larger size. The reproductive investment as measured by GSI was higher in the WC squid. Much of the variability in age and size-at-maturity of females in the population was due to differences between cohorts but this was not the case for males.

The population biology of Loligo vulgaris and Loligo forbesi in Galician waters is described based on monthly samples from the fishery obtained during the period February 199 l-June 1992. Maturity was assessed using a maturity scale and indices. The estimated number of oocytes in mature females varied from 782 to 21 885 in L. vulgaris and from 1317 to 14 956 in L. forbesi, and showed a slight positive correlation with the length of the mantle (ML) for both species. Oocytes in the ovaries fall into three discrete size classes, which suggests that L. vulgaris and L.forbesi are intermittent or multiple spawning species. In L. vulgaris males mature at two different modal sizes, hence perhaps at two different ages, while in L. forbesi this occurs in both males and females. Males mature earlier in the season than females in both species. The maximum number of spermatophores found was 1010 and 1000 in two L. vulgaris males with 119 mm and 400 mm ML respectively, and 1035 in a L. forbesi male with 150 mm ML. In both species, spermatophore length increases with ML. Loligo forbesi males maturing at a larger size produce fewer but larger spermatophores than those maturing at a small size. Loligo vulgaris spawn throughout the year, but the period of more intensive spawning extends from December to April. The breeding season ofL. forbesi extends from December to May, the more intensive spawning extending from December to February. Sex ratios were variable for both species. Age and growth for both species and sexes were estimated by examining growth increments in the statoliths. Like-sized individuals had different ages in both species. The life span of L.

Coloration is a trait frequently cited as important to ecological, and thus evolutionary, processes in amphibians. To fully understand the impact of coloration, a consistent method of color measurement is required, which is often achieved by collecting color information in a captive, laboratory setting. However, results from the lab can only be generalized to the field if coloration remains consistent between the two. In this study we collected spectral data from two discrete color morphs of Plethodon cinereus (erythristic and striped) at two distinct time periods while in captivity to determine whether and how their coloration changed over time. We found that brightness in both color morphs decreased similarly through time, though the change was most pronounced in the erythristic morph. Additionally, we examined the overall coloration change over time using multivariate change vectors and found that the magnitude (amount) of multivariate color change was significantly greater in the erythristic morph as compared to the striped morph (for cheek color patches). Intriguingly, the direction of color change in color space was oriented similarly among measured regions within each morph, whereas the direction of color change differed between morphs, indicating that while coloration changed for all individuals, how that change occurred was morph-specific. We propose a physiological mechanism that may be responsible for the observed changes, and suggest several additional mechanisms that may influence labile coloration in these salamanders. Additionally, our findings suggest that quantifying color from individuals held in captivity should be used with caution, as color changes observed in a laboratory setting may not reflect what is seen in the field. ; and (DCA) dcadams@iastate.edu. Send reprint requests to ACK.

The reproductive pattern of Loligo vulgaris and Loligo forbesi was studied on the basis of gonad maturation, mating and spawning in males and females of both species which were present off the northwest coast of Spain (Galicia), between February 1991 and February 1993. The mature females of both species have several modes of egg sizes and developmental stages within the ovary. Several signs indicate that both female Loligo vulgaris and L. forbesi undergo partial ovulation at the time of spawning, the spawning period being relatively long, although in no case representing the greatest fraction of the animal's life before death. Egg-laying occurring in separate batches and somatic growth between egg batchs has not been observed. This reproductive pattern is defined as intermittent terminal spawning. Some other terms describing different cephalopod reproductive strategies are also defined.