Animal Ecology

SUPPORT FOR THE IMMUNOCOMPETENCE HANDICAP HYPOTHESIS IN THE WILD: HORMONAL MANIPULATION DECREASES SURVIVAL IN SICK DAMSELFLIES

by Roberto Munguia-Steyer

Daniel M. González-Tokman, Roberto Munguía-Steyer, Isaac González-Santoyo, Fernanda S. Baena-Díaz, Alex Córdoba-Aguilar. Evolution. DOI: 10.1111/j.1558-5646.2012.01678.x

The immunocompetence handicap hypothesis (ICHH) states that hormones enhance sexual trait expression but impair... more The immunocompetence handicap hypothesis (ICHH) states that hormones enhance sexual trait expression but impair immunity. Previous tests of the ICHH have been hampered by experimental design problems. Here we report on an experimental test of the ICHH that includes manipulations of both hormones and infections in males of the territorial damselfly, Hetaerina americana, with accurate survival measurements. We conducted a fully factorial experiment subjecting each individual to one of three topical treatments: methoprene (a juvenile hormone analog), acetone, or control, and one of three injection treatments: bacteria, PBS, or control. We measured survival of manipulated males in both the wild and in captivity. As predicted, survival was most heavily impaired in methoprene-bacteria males than in the other groups in the wild, and no survival differences emerged in captive animals. This result confirms that survival is one cost an animal pays for increased hormonal levels. This corroborates theoretical predictions of the ICHH.

From migration to nomadism: movement variability in a northern ungulate across its latitudinal range

by Luca Börger

Ecological Applications (in print) Co-authored with Navinder Singh (first author), Nils Bunnefeld, Holger Detki, and Goran Ericsson.

This is the first proper application of my net-squared displacement approach for modelling animal movements (Borger & Fryxell 2012).
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Understanding the causes and consequences of animal movements is of fundamental biological interest because any... more Understanding the causes and consequences of animal movements is of fundamental biological interest because any alteration in movement can have direct and indirect effects on ecosystem structure and function. It is also crucial for assisting spatial wildlife management under variable environmental change scenarios. Recent research has highlighted the need of quantifying individual variability in movement behavior and how it is generated by interactions between individual requirements and environmental conditions, to understand the emergence of population level patterns. Using a multi-annual movement dataset of 213 individual moose (Alces alces) across a latitudinal gradient (from 56° to 67° N) that spans over 1,100 km of varying environmental conditions, we analyze the differences in individual and population level movements. We tested the effect of climate, risk and human presence in the landscape on moose movements. The variation in these factors explained the existence of multiple movements (migration, nomadism, dispersal, sedentary) among individuals and seven populations. Hence, heterogeneity in the immediate environment can result in multiple movements within a species. Population differences were primarily related to latitudinal variation in snow depth and road density. Individuals showed both fixed and flexible behaviors across years, and were less likely to migrate with age in interaction with snow and roads. For the predominant movement strategy, migration, the distance, timing and duration at all latitudes varied between years. Males traveled longer distances and began migrating earlier in spring than females. Our study provides strong quantitative evidence for the dynamics of animal movements in response to changes in environmental conditions along with varying risk from human influence across the landscape. For moose, given its wide distributional range, changes in the distribution and migratory behavior are expected under future warming scenarios.

A Predictive Model to Differentiate the Fruit Bats Cynopterus brachyotis and C. cf. brachyotis Forest (Chiroptera: Pteropodidae) from Malaysia Using Multivariate Analysis. 2012

by M.T. Abdullah, PhD

Read also Abdullah (2003)

Field discrimination of Cynopterus brachyotis and C. cf. brachyotis Forest (as designated by Francis 2008) in southern... more Field discrimination of Cynopterus brachyotis and C. cf. brachyotis Forest (as designated by Francis 2008) in southern Thailand, Peninsular Malaysia, and Borneo is problematic. These 2 forms are sympatric in this region but are confined to different habitat types: C. brachyotis inhabits open habitats, orchards, and agricultural areas, while C. cf. brachyotis Forest is confined to primary and old secondary forests. In this study, we attempted to develop prediction models to identify both C. brachyotis and C. cf. brachyotis Forest in this region based on multivariate statistics. Two predictive models were generated using a canonical discriminant function, and it was found that 5 characters can be used to accurately identify museum vouchers of C. brachyotis and C. cf. brachyotis Forest. Four characters are needed for field identification of these 2 forms of Cynopterus in southern Thailand, Peninsular Malaysia, and Borneo. A review of the current taxonomy and classification indicated that there is a need to describe the 6 existing forms of the C. brachyotis complex in the Indo-Malayan region. This will aid conservationists, field ecologists, and taxonomists in taxonomic- and conservation-related decisions about this species complex.

Is translocation a management tool?

by M.T. Abdullah, PhD

Comparison of density estimation methods for mammal populations with camera traps in the Kaa-Iya del Gran Chaco landscape

by Alfredo Romero-Muñoz

Noss, A. J., Gardner, B., Maffei, L., Cuéllar, E., Montaño, R., Romero-Muñoz, A., Sollman, R., O'Connell, A. F. (2012).  Animal Conservation. doi: 10.1111/j.1469-1795.2012.00545.x

Sampling animal populations with camera traps has become increasingly popular over the past two decades, particularly... more Sampling animal populations with camera traps has become increasingly popular over the past two decades, particularly for species that are cryptic, elusive, exist at low densities or range over large areas. The results have been widely used to estimate population size and density. We analyzed data from 13 camera trap surveys conducted at five sites across the Kaa-Iya landscape, Bolivian Chaco, for jaguar, puma, ocelot and lowland tapir. We compared two spatially explicit capture–recapture (SCR) software packages: secr, a likelihood-based approach, and SPACECAP, a Bayesian approach, both of which are implemented within the R environment and can be used to estimate animal density from photographic records of individual animals that simultaneously employ spatial information about the capture location relative to the sample location. As a non-spatial analysis, we used the program CAPTURE 2 to estimate abundance from the capture–recapture records of individuals identified through camera trap photos combined with an ad hoc estimation of the effective survey area to estimate density. SCR methods estimated jaguar population densities from 0.31 to 1.82 individuals per 100 km2 across the Kaa-Iya sites; puma from 0.36 to 7.99; ocelot from 1.67 to 51.7; and tapir from 7.38 to 42.9. Density estimates using either secr or SPACECAP were generally lower than the estimates generated using the non-spatial method for all surveys and species; and density estimates using SPACECAP were generally lower than that using secr. We recommend using either secr or SPACECAP because the spatially explicit methods are not biased by an informal estimation of an effective survey area. Although SPACECAP and secr are less sensitive than non-spatial methods to the size of the grid used for sampling, we recommend grid sizes several times larger than the average home range (known or estimated) of the target species.

Overwintering sites of the Japanese carrion beetle Eusilpha japonica

by Tadao Hirota

Population structure of the large Japanese field mouse, Apodemus speciosus (Rodentia: Muridae), in suburban landscape, based on mitochondrial D-loop sequences: GENE FLOW OF FIELD MOUSE IN SUBURBAN LANDSCAPE

by Tadao Hirota

The "cultural filter," human transport of mussel shell, and the applied potential of zooarchaeological data

by Steve Wolverton

Peacock, Randklev, Wolverton, Palmer, Zaleski forthcoming in Ecological Applications

Large assemblages of animal bones and/or shells from archaeological sites can provide data valuable for modern... more Large assemblages of animal bones and/or shells from archaeological sites can provide data valuable for modern conservation efforts, e.g., by providing accurate historical baselines for species reintroductions or habitat restoration. Such data are underused by natural scientists, partly due to assumptions that archaeological materials are too biased by prehistoric human actions (the so-called "cultural filter") to accurately reflect past biotic communities. In order to address many paleobiological, archaeological, or applied research questions, data on past species, communities, and populations must first be demonstrated to be representative at the appropriate level. We discuss different ways in which one kind of cultural bias, human transport of specimens, can be tested at different scales, using freshwater mussel shells from prehistoric sites in the Tombigbee River basin of Mississippi and Alabama to show how representativeness of samples can be assessed.


Read More: http://www.esajournals.org/doi/abs/10.1890/11-1943.1

Group decision-making in chacma baboons: leadership, order and communication during movement

by Cedric Sueur

Soulsbury, C.D., Alatalo, R.V., Lebigre, C. & Siitari, H. (2012) Restrictive mate choice criteria causes age-specific inbreeding in female black grouse Tetrao tetrix. Animal Behaviour.

by Carl Soulsbury

Online early

Inbreeding is generally rare in large, natural populations yet mate choice often appears to be random with respect to... more Inbreeding is generally rare in large, natural populations yet mate choice often appears to be random with respect to kinship. This suggests that the risks of inbreeding may be small because passive mechanisms of inbreeding avoidance, for example dispersal, are effective at lowering inbreeding risk. Previous theoretical and empirical studies have assumed that the risks of inbreeding are constant over an individual's life span, but in the lek-breeding black grouse, inbreeding increases with female age. To determine whether inbreeding avoidance mechanisms are also age dependent, we generated four null models of random mate choice ranging from complete randomness to more biologically realistic mate choice criteria and compared these to 8 years of data on inbreeding levels at four different female age classes. We additionally tested whether mate fidelity decreased inbreeding risk. Observed inbreeding in female age classes 1, 2 or ≥3 were not significantly different from random, but was approximately 3.5 times higher in female age class ≥4. Alternative models using mate choice criteria showed no significant differences between observed and expected levels for any age class. Our results are in line with previous studies on noncooperatively breeding passerine birds, which indicate that mating is random with respect to kinship and that increased inbreeding in older females can be explained by reduced male availability caused by restrictive mate choice criteria. We also found that individuals that switched mates significantly increased relatedness to partners suggesting that mate fidelity may have evolved as an important passive inbreeding avoidance mechanism.

Ethnobiology as a Bridge between Science and Ethics: An Applied Paleozoological Perspective

by Steve Wolverton

In Ethnobiology. Edited by E. N. Anderson, D. Pearsall, E. Hunn, and N. Turner 2011, pp. 115-132. Wiley-Blackwell. John Wiley & Sons, Inc.

In the face of the global environmental crisis, ethnobiologists find themselves in a potentially helpful position.... more In the face of the global environmental crisis, ethnobiologists find themselves in a potentially helpful position. Ethnobiology represents one of a few bridging disciplines between the philosophical foundations of environmental ethics and the scientific foundations of environmental science. Environmental philosophers study what ought to be done to address environmental problems at multiple spatial and temporal scales (Borgerhoff-Mulder and Coppolillo 2005; Rolston 1988), focusing on what it means to value nature, how humans do value and should go about valuing nature, and how these ethical footings should inform science and policy. Environmental science incorporates functional roles for many scientific disciplines (Miller 2007). Environmental science and environmental ethics share the goal of curbing the environmental crisis through communication among practitioners from different fields, appreciation of diverse perspectives, and incorporation of vested parties in policies and management decisions (Penn and Mysterud 2007a). Practitioners of ethnobiology communicate and interact across disciplinary, cultural, and temporal boundaries (Lepofsky 2009; Nabhan 2009).Within ethnobiology, applied zooarchaeology (or “applied paleozoology” to include paleontology)—the study of animal remains from archaeological and paleontological sites to provide baseline information relevant to restoration ecology and conservation biology—transcends temporal boundaries and offers an example of a bridging perspective that links ethics to science.

Reliance on prey derived nitrogen by the carnivorous plant Drosera rotundifolia decreases with increasing nitrogen deposition.

by Jonathan Millett

Millett J, Svensson BM, Newton J, Rydin H. 2012. New Phytologist. doi: 10.1111/j.1469-8137.2012.04139.x

• Carnivory in plants is presumed to be an adaptation to a low nutrient environment. Nitrogen (N) from carnivory is... more • Carnivory in plants is presumed to be an adaptation to a low nutrient environment. Nitrogen (N) from carnivory is expected to become a less important component of their N budget as root N availability increases.
• We investigated the uptake of N via roots versus prey of the carnivorous plant Drosera rotundifolia growing in ombrotrophic bogs along a latitudinal nitrogen deposition gradient through Sweden, using a natural abundance stable isotope mass balance technique.
• D. rotundifolia plants receiving the lowest level of N deposition obtained a greater proportion of N from prey (57%) than plants on bogs with higher N deposition (22% at intermediate and 33% at the highest deposition). When adjusted for differences in plant mass this pattern was also present when considering total prey N uptake (66, 26 and 26 µg prey N plant-1 at the low, intermediate and high N deposition sites respectively). The pattern of mass adjusted root N uptake was opposite to this (47, 75 and 86 µg N plant-1).
• D. rotundifolia plants in this study switched from reliance on prey N to reliance on root derived N as a result of increasing N availability due to atmospheric N deposition.

Macrophyte structural complexity influences spider assemblage attributes in wetlands

by Roger Paulo Mormul

Wetlands 2012

Macrophytes increase structural complexity in aquatic ecosystems and their emergent structures provide habitats for... more Macrophytes increase structural complexity in aquatic ecosystems and their emergent structures provide habitats for spiders. We sampled spiders in three species of macrophytes (Eichhornia azurea, Eichhornia crassipes and Limnobium laevigatum) and measured five traits indicative of structural complexity: horizontal structure, vertical structure, plant height, macrophyte richness and macrophyte biomass. We tested the hypothesis that spider density and diversity increase and guild composition changes along a gradient of structural complexity provided by macrophytes. Vertical and horizontal structure and macrophyte richness covaried with the attributes of spider assemblages. However, vertical structure was an important habitat-complexity trait because it covaried with all spider attributes investigated, positively affecting density and taxa richness and changing guild composition. Our findings suggest that the increase in macrophyte structural complexity, primarily through vertical structure, provides additional habitat and microhabitat variability. These forms of variability may increase the availability of prey and shelter and even reduce intraguild predation between spiders, thereby potentially increasing density and taxa richness. Moreover, an increase in vertical complexity provides available structures for web attachment, favoring web-building spiders and consequently affecting guild composition. Thus, habitat structure plays an important role in structuring spider assemblages and specific traits may mediate changes in particular attributes of spider assemblages.

Antics of ants: Ants as agents of bioturbation in a midden deposit in southeastern Queensland (PROOF)

by Andrew Robins

Robins, R. & Robins, A. "The antics of ants: ants as agents of bioturbation in a midden deposit in Southeast Queensland". Environmental Archaeology, 16(2),pp. 151-161 http://www.ingentaconnect.com/content/maney/env/2011/00000016/00000002/art00007?crawler=true

During salvage excavations of an Aboriginal shell midden at Hollywell, on the Gold Coast of Queensland, ant activity... more During salvage excavations of an Aboriginal shell midden at Hollywell, on the Gold Coast of Queensland, ant activity was noted as a contributor to both bioturbation, and to the introduction of modern material, including metal fragments, plastic, nylon fishing line and cotton thread into the deposit. This material was found at depths of up to 400 mm and adjacent to excavation units with shells with a calibrated age of 1050–900 BP. These observations prompted the development of a small experiment to illustrate the impact that one species of common Australian ant observed on site, the green-head ant (Rhytidoponera metallica), can have on cultural material in sandy deposits.

Conventional tagging and acoustic telemetry of a small surgeonfish, Zebrasoma flavescens, in a structurally complex coral reef environment

by Jeremy T. Claisse

Claisse, J.T., T.B. Clark, B.D. Schumacher, S.A. McTee, M.E. Bushnell, C.K. Callan, C.W.  Laidley and J.D. Parrish (2011) Conventional tagging and acoustic telemetry of a small surgeonfish, Zebrasoma flavescens, in a structurally complex coral reef environment. Environmental Biology of Fishes. 91:185-201

Выпуск ондатры на Демьянке: Эпизод из научной биографии И.И. Барабаш-Никифорова

by Vladimir Adaev

Spawn and larval development of Pleuroploca aurantiaca (Lamarck, 1816)(Gastropoda: Fasciolariidae) from Northeast Brazil| Puesta y desarrollo larvario de …

by Carlos Meirelles

Monitoring the breeding behavior of Javan Hawk Eagle Spizaetus bartelsi using camera surveillance (CCTV) at Ciasem – Tangkuban Perahu Nature Reserve, West Java, Indonesia

by Zaenal Mutaqien

Co-authored with Ade Rahmat, Zaini Rakhman, Fassa Faisal, Yogi Satoto, Asep Maman Sukirman. Published in Proceeding of the 4th Asian Raptor Research and Conservation Network (ARRCN) Symposium. Kuala Lumpur. 2005.

One of the important periods in the life cycle of javan Hawk Eagle is its breeding period. However, during this period... more One of the important periods in the life cycle of javan Hawk Eagle is its breeding period. However, during this period the eagles are very sensitive to any kind of disturbance from human activities, including the observation of its breeding behavior by researchers. To eliminates human disturbance during this period, observation of breeding behavior of a couple of Javan Hawk Eagle in Panaruban-Tangkuban Perahu Mountain in the Ciasem-Tangkuban Perahu Nature Reserve was conducted using closed circuit surveillance camera (CCTV) methods. Two surveillance camera `were installed on the tree adjacent to the nest with each camera located at the distances of about 20 m and 50 m respectively from the nest. Each camera was wired-connected to a monitor screen and recorder at our base camp 500 meters located from the nest tree. Electricity to operate the camera surveillance, was generated using an environmental-friendly electricity through a ‘pico hydro’ (mini-hydro) system, the installation was carried out on May 24-25, 2003 before the eggs-lying period and intensive continuous monitoring was carried out through camera surveillance for three months from May- August, 2003.

Inter- and intra-plant variations in nitrogen, tannins and shoot growth of Sclerocarya birrea browsed by elephants

by Peter Scogings

Scogings, P.F., Taylor, R. & Ward, D. 2012. Inter- and intra-plant variations in nitrogen, tannins and growth of Sclerocarya birrea browsed by elephants. Plant Ecology 213: 483-491.

Impacts of elephants (Loxodonta africana africana) on woody vegetation has attracted substantial attention for... more Impacts of elephants (Loxodonta africana africana) on woody vegetation has attracted substantial attention for decades, but plant-level responses remain a gap in the understanding of savanna ecology. Marula (Sclerocarya birrea caffra) forms an important part of elephant diets. We investigated the relationships between browsing intensity and shoot/leaf size, nitrogen (N) and condensed tannin (CT) concentrations in upper and lower canopies of male and female marula individuals in Hluhluwe-iMfolozi Park, South Africa. Browsing intensity (54%) did not differ between sexes, suggesting no preference by elephants for either sex. Females had higher [CT] than males and tannin decreased with increasing browsing intensity in both sexes. In lightly or moderately browsed trees, [CT] was controlled by unmeasured factors such that within-tree impacts of browsing were more variable in lightly/moderately browsed than heavily browsed trees. There was little change in [N] up to 60% browsing intensity, but [N] increased dramatically at higher intensity. Shoots and leaves on broken branches in the lower canopy were larger (2.5 and 1.2 times, respectively) than those on unbroken branches in either upper or lower canopies. Chemical responses were systemic and potentially influence browsing among trees, while growth responses were strongly localised and potentially influence browsing within trees. Although marula trees are able to compensate vigorously for browsing at the scale of individual organs, trees may become progressively carbon-deficient and have their lives shortened if total plant growth is negatively affected by chronic browsing, e.g. near permanent water.

Energy Beyond Food: Foraging Theory Informs Time Spent in Thermals by a Large Soaring Bird

by Sergio Lambertucci

Shepard, E.L.C., S.A. Lambertucci, D. Vallmitjana and R.P. Wilson. 2011. Energy beyond food: Foraging theory informs time spent in thermals by a large soaring bird. PLos ONE 6(11): e27375. doi:10.1371/journal.pone.0027375

Current understanding of how animals search for and exploit food resources is based on microeconomic models. Although... more Current understanding of how animals search for and exploit food resources is based on microeconomic models. Although widely used to examine feeding, such constructs should inform other energy-harvesting situations where theoretical assumptions are met. In fact, some animals extract non-food forms of energy from the environment, such as birds that soar in updraughts. This study examined whether the gains in potential energy (altitude) followed efficiency-maximising predictions in the world’s heaviest soaring bird, the Andean condor (Vultur gryphus). Animal attached technology was used to record condor flight paths in three-dimensions. Tracks showed that time spent in patchy thermals was broadly consistent with a strategy to maximise the rate of potential energy gain. However, the rate of climb just prior to leaving a thermal increased with thermal strength and exit altitude. This suggests higher rates of energetic gain may not be advantageous where the resulting gain in altitude would lead to a reduction in the ability to search the ground for food. Consequently, soaring behaviour appeared to be modulated by the need to reconcile differing potential energy and food energy distributions. We suggest that foraging constructs may provide insight into the exploitation of non-food energy forms, and that non-food energy distributions may be more important in informing patterns of movement and residency over a range of scales than previously considered.