Abstract View

Christine Nießner, Susanne Denzau, Katrin Stapput, Margaret Ahmad, Leo Peichl, Wolfgang Wiltschko, and Roswitha Wiltschko
Magnetoreception: activated cryptochrome 1a concurs with magnetic orientation in birds
J. R. Soc. Interface November 6, 2013 10 88 20130638; doi:10.1098/rsif.2013.0638 1742-5662

The radical pair model proposes that the avian magnetic compass is based on radical pair processes in the eye, with cryptochrome, a flavoprotein, suggested as receptor molecule. Cryptochrome 1a (Cry1a) is localized at the discs of the outer segments of the UV/violet cones of European robins and chickens. Here, we show the activation characteristics of a bird cryptochrome in vivo under natural conditions. We exposed chickens for 30 min to different light regimes and analysed the amount of Cry1a labelled with an antiserum against an epitope at the C-terminus of this protein. The staining after exposure to sunlight and to darkness indicated that the antiserum labels only an illuminated, activated form of Cry1a. Exposure to narrow-bandwidth lights of various wavelengths revealed activated Cry1a at UV, blue and turquoise light. With green and yellow, the amount of activated Cry1a was reduced, and with red, as in the dark, no activated Cry1a was labelled. Activated Cry1a is thus found at all those wavelengths at which birds can orient using their magnetic inclination compass, supporting the role of Cry1a as receptor molecule. The observation that activated Cry1a and well-oriented behaviour occur at 565 nm green light, a wavelength not absorbed by the fully oxidized form of cryptochrome, suggests that a state other than the previously suggested Trp•/FAD• radical pair formed during photoreduction is crucial for detecting magnetic directions.

Schoech SJ, Bowman R, Hahn TP, Goymann W, Schwabl I, Bridge ES. 2013. The effects of low levels of light at night upon the endocrine physiology of western scrub-jays (Aphelocoma californica). J. Exp. Zool. 9999:1–12.
Florida scrub-jays (Aphelocoma coerulescens) in the suburbs breed earlier than jays in native habitat. Amongst the possible factors that influence this advance (e.g., food availability, microclimate, predator regime, etc.), is exposure to artificial lights at night (LAN). LAN could stimulate the reproductive axis of the suburban jays. Alternatively, LAN could inhibit pineal melatonin (MEL), thus removing its inhibitory influence on the reproductive axis. Because Florida scrub-jays are a threatened species, we used western scrub-jays (Aphelocoma californica) to investigate the effects of LAN upon reproductive hormones and melatonin. Jays were held under conditions in which the dark-phase of the light:dark cycle was without illumination and then under low levels of LAN. Under both conditions, birds were exposed first to short-days (9.5L:14.5D) that were gradually increased to long-days (14.5L:9.5D). At various times, blood samples were collected during the light part of the cycle to measure reproductive hormones (luteinizing hormone, LH; testosterone, T; and estradiol, E2). Similarly, samples to assess melatonin were collected during the dark. In males, LAN caused a depression in LH levels and levels were ∼4× greater under long- than short-days. In females, there was no effect of LAN or photoperiod upon LH. LAN resulted in depressed T levels in females, although there was no effect on T in males. E2 levels in both sexes were lower under LAN than under an unlighted dark-phase. Paradoxically, MEL was higher in jays under LAN, and under long-days. MEL did not differ by sex. LAN disrupted the extraordinarily strong correlation between T and E2 that existed under unlighted nocturnal conditions. Overall, our findings fail to support the hypothesis that LAN stimulates the reproductive axis. Rather, the data demonstrate that LAN tends to inhibit reproductive hormone secretion, although not in a consistent fashion between the sexes.

Peter Schippers, Astrid J.A. van Teeffelen, Jana Verboom, Claire C. Vos, Koen Kramer, Michiel F. WallisDeVries, The impact of large herbivores on woodland–grassland dynamics in fragmented landscapes: The role of spatial configuration and disturbance, Ecological Complexity, Available online 23 August 2013, ISSN 1476-945X, http://dx.doi.org/10.1016/j.ecocom.2013.07.002.
The vegetation structure of natural ecosystems is usually considered independent of their size and their location in the landscape. In this study, we examine the effect of size, spatial configuration and disturbances on the dynamic interactions of large herbivores and vegetation in a patchy environment using a metapopulation model. Simulations indicate that small, isolated or unfenced patches have low herbivore numbers and high tree cover whereas large, well-connected or fenced patches support high herbivore densities and are covered by grassland. Recovery of both herbivore numbers and forest cover in response to disturbance is slow (> 100 years). These long recovery times are partly attributable to negative feedbacks between herbivore numbers and tree cover. When the population of large herbivores is disturbed, forest is able to expand, subsequently inhibiting herbivore population recovery. Likewise, forest disturbance allows herbivore population expansion, which inhibits forest recovery. Additionally, infrequent and limited disturbances like hunting and forest removal also affect the vegetation cover in patches of nature. Thus, our work indicates that the location and size of patches, together with disturbances, largely determine the structure of the vegetation in fragmented landscapes.

Wolf Howling Is Mediated by Relationship Quality Rather Than Underlying Emotional Stress
Francesco Mazzini, Simon W. Townsend, Zsófia Virányi, Friederike Range
Current Biology – 22 August 2013

We investigated the influence of social and physiological factors on wolf howling. Wolves howl more to keep contact with affiliated partners and with pack leaders. Howling is mediated by the social relationship not cortisol level of the howlers. This pattern indicates that wolves have some voluntary control of their howling.
While considerable research has addressed the function of animal vocalizations, the proximate mechanisms driving call production remain surprisingly unclear. Vocalizations may be driven by emotions and the physiological state evoked by changes in the social-ecological environment, or animals may have more control over their vocalizations, using them in flexible ways mediated by the animal’s understanding of its surrounding social world. While both explanations are plausible and neither excludes the other, to date no study has attempted to experimentally investigate the influence of both emotional and cognitive factors on animal vocal usage. We aimed to disentangle the relative contribution of both mechanisms by examining howling in captive wolves. Using a separation experiment and by measuring cortisol levels, we specifically investigated whether howling is a physiological stress response to group fragmentation and whether it is driven by social factors, particularly relationship quality. Results showed that relationship quality between the howler and the leaving individual better predicted howling than did the current physiological state. Our findings shed important light on the degree to which animal vocal production can be considered as voluntary.

Zootaxa 3702 (2): 101–123 (26 Aug. 2013)
Re-evaluating the taxonomic status of Chiromantis in Thailand using multiple lines of evidence (Amphibia: Anura: Rhacophoridae)

Because of general phenotypic similarities and distribution of species across two continents, the genus Chiromantis has proven somewhat enigmatic. Among Indochinese species, the validity of C. hansenae has been questioned by some who consider it a junior synonym of C. vittatus. We employ three lines of evidence to elucidate the taxonomic status and phylogenetic relationships of four congeneric species of Chiromantis frogs from Thailand. Results of molecular, morphological, and bioacoustic data analyses support at least four evolutionarily distinct and monophyletic clades: C. doriae, C. nongkhorensis, C. vittatus and C. hansenae. Genetic divergence between C. vittatus and C. hansenae is >10%, significantly greater than C. doriae
and C. nongkhorensis (4.5%). Our results support the taxonomic validity of C. hansenae and suggest that there may be more diversity within C. hansenae and C. vittatus than is currently recognized.

Zootaxa 3702 (2): 159–178 (26 Aug. 2013)
Sphyrna gilberti sp. nov., a new hammerhead shark (Carcharhiniformes, Sphyrnidae) from the western Atlantic Ocean

Sphyrna gilberti sp. nov. is described based on 54 specimens collected in the coastal waters of South Carolina, U.S.A. Morphologically, S. gilberti sp. nov. is separable from S. lewini (Griffith & Smith 1834) only in the number of precaudal vertebrae. Due to rarity of specimens and the highly migratory behavior of most sphyrnids, the range of S. gilberti sp. nov. is unknown.

Christina Rockwell, Pia O. Gabriel, Jeffrey M. Black, Foraging dynamics in Steller’s jays: size and viability of cacheable food items, Animal Behaviour, Available online 23 August 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.07.018.Several species of birds and mammals cache food items, which in harsh conditions may translate into improved survival or reproductive success. Animals may benefit from evaluating the quality of cache items in terms of size, nutrition and storage viability. Steller’s jays, Cyanocitta stelleri, which cache seeds for later consumption, may handle multiple food items with their beak prior to making a selection. By picking items up, individuals may use visual and tactile cues to evaluate size and shell condition. The number of items an individual jay handles is repeatable, reflecting consistent individual-specific foraging behaviours that may differentiate success at selecting high-quality cache items. In this study we quantified population-level preferences for food items based on size and shell integrity, and individual Steller’s jay sampling behaviour when presented with these choices. Using field trials with free-ranging subjects, we quantified sampling frequency in a variety of choice tests and measured individuals‘ success at choosing higher-quality items. We found that Steller’s jays selected items of greater weight and items with intact shells, and preferences for these properties were of comparable magnitude. Jays sampled more nuts during choice sets involving cracked and intact shells, resulting in individuals selecting more profitable nuts for caching. These results may suggest that Steller’s jays evaluate cache items based on both current and future expected energetic values, and that sampling behaviour may enable them to choose more valuable forage items.

R. Tewari and G. S. Rawat, “Studies on the Food and Feeding Habits of Swamp Deer (Rucervus duvaucelii duvaucelii) in Jhilmil Jheel Conservation Reserve, Haridwar, Uttarakhand, India,” ISRN Zoology, vol. 2013, Article ID 278213, 6 pages, 2013. doi:10.1155/2013/278213
Food habits of the swamp deer (Rucervus duvaucelii duvaucelii) were studied in and around Jhilmil Jheel Conservation Reserve (JJCR), Uttarakhand, for two years. This population (320 in number) was recently rediscovered in the state (2005) and warranted an ecological study because the habitat around this study area is heavily fragmented due to expansion of agriculture, habitation, and various other land use practices. Therefore, this study was initiated by the major objective of studying seasonal variation in food habits of swamp deer. Proportionate food consumption was studied using feeding quadrat method. The study reveals that the overall diet of swamp deer consisted mainly of graminoids (grasses and sedges) and herbs (terrestrial and aquatic). In the protected areas studied earlier, the swamp deer habitat was dominated by grasses, and hence they were reported to be predominantly a grazer who occasionally fed on aquatic plants (Schaller 1967 and others). In contrast, at Jhilmil, the area also has equal presence of other plant types namely, sedges and terrestrial herbs. This resulted in polyphagous feeding habit of animal here.

Christopher N. Templeton, Nigel I. Mann, Alejandro A. Ríos-Chelén, Esmeralda Quiros-Guerrero, Constantino Macías Garcia, Peter J.B. Slater, An experimental study of duet integration in the happy wren, Pheugopedius felix, Animal Behaviour, Available online 24 August 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.07.022.
Pairs of duetting birds can sing coordinated duets with such precision that they are often mistaken for a single individual, yet little is known about how this impressive temporal synchronization is achieved. We experimentally examined duet coordination in male happy wrens, held briefly in captivity, by playing song phrases from their partner at different distances and tempos. Males were more likely to respond to songs played nearby, but did not vary their amplitude to compensate for their partner’s simulated distance. Males modified their song rate to match the manipulated female playback tempo, indicating that they listen and respond to each female utterance. Each happy wren has a sex-specific repertoire of about 40 different song phrases and pairs combine particular phrases according to pair-specific duet ‘codes’, creating a further challenge for coordinating duets. We found that most males produced the appropriate phrase to reply to the female playback song in the absence of any other potential cues, sometimes delivering the correct song phrase type within 0.5 s of the start of the very first female playback heard. These experiments demonstrate rapid decision making and vocal production, indicative of sophisticated underlying cognitive processing, and provide a novel experimental technique to investigate the mechanisms controlling vocal duets.

Andrea Flack, Zsuzsa Ákos, Máté Nagy, Tamás Vicsek, Dora Biro, Robustness of flight leadership relations in pigeons, Animal Behaviour, Available online 24 August 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.07.005.
Collective animal movements produce spectacular natural phenomena that arise from simple local interactions among group members. Flocks of homing pigeons, Columba livia, provide a useful model for the study of collective motion and decision making. During homing flights, flock members are forced to resolve potentially divergent navigational preferences in order to stay together and benefit from flying in a group. Recent work has demonstrated that some individuals consistently contribute more to the movement decisions of the flock than others do, thereby generating stable hierarchical leader–follower networks. Yet, what attributes of a flying pigeon reliably predict leadership remains an open question. We examined the flexibility of an individual’s hierarchical leadership rank (i.e. its ordinal position when flock members are ranked according to the average time differences with which they lead or follow others) as a function of changes in its navigational knowledge. We manipulated already established hierarchical networks in three different flocks, by providing certain individuals with additional homing experience. We found that such training did not consistenly lead to an increase in birds‘ leadership ranks, and that, in general, the nature of leader–follower interactions between trained and untrained birds remained unaffected. Thus, leadership hierarchies in pigeon flocks appear resistant to changes in the navigational knowledge of a subset of their members, at least when these changes are relatively small. We discuss the implications of our results in light of the potential benefits of structural stability in decision-making networks.

Guy A. Balme, Luke T.B. Hunter, Why leopards commit infanticide, Animal Behaviour, Available online 24 August 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.07.019.
Infanticide is a widespread but seldom observed behaviour that has been shown to convey strong selection forces on some social mammals. However, infanticide in nonsocial species is less clearly understood, particularly the evolutionary function of infanticide. Here we present direct and indirect evidence of infanticide in a large, solitary felid, the African leopard, Panthera pardus, and determine its likely causes in light of six explanatory hypotheses. Observed and inferred rates of infanticide for leopards were among the highest recorded for mammalian carnivores, accounting for almost half of juvenile mortality and nearly a third of all offspring. Our results demonstrate that infanticide in leopards is mainly an adaptive behaviour which provides reproductive benefits to perpetrators. Infanticidal males were typically unrelated to their victims, the death of unweaned offspring shortened the interbirth intervals of mothers, and perpetrators increased their chances of mating with and siring the mother’s subsequent litter. Female leopards also appear to have developed a profusion of strategies to counter the risk of infanticide, providing further support for the sexual selection hypothesis. Cannibalism may provide some incentive for infanticide (perpetrators usually consumed their victims) but this is probably an added, minor benefit rather than the primary driver for the behaviour. Our findings suggest that infanticide is a key factor shaping the sociospatial ecology of leopards. They also highlight the importance of accounting for functional components of population dynamics when managing large carnivores, particularly for invasive activities that artificially elevate adult male turnover.

Alex M. Thompson, Amanda R. Ridley, Philip A.R. Hockey, Fiona M. Finch, Adam Britton, Nichola J. Raihani, The influence of siblings on begging behaviour, Animal Behaviour, Available online 24 August 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.07.021.
Elaborate solicitation displays are a common feature of interactions between care-givers and offspring. These displays are interpreted as the phenotypic expression of the conflict of interests between parents and offspring over parental investment. Offspring typically have siblings and thus do not exist in isolation. Therefore, they may adjust their begging in response to their siblings‘ begging, either competitively or cooperatively. Alternatively, begging may be independent of the begging efforts of siblings. Studies of avian begging have primarily focused on nestlings, where offspring are immobile and compete directly over the allocation of parental resources. We investigated the influence sibling begging had on individual fledgling begging in the cooperatively breeding pied babbler, Turdoides bicolor. Using experimental manipulations, we found that fledgling begging behaviour was negatively correlated with satiation and unrelated to the begging effort of siblings. Pied babbler care-givers were able to target increased provisioning to individuals with artificially increased demand while maintaining provisioning rates to the rest of the brood. Thus, fledglings were found to incur no provisioning costs or benefits from either increased or decreased begging by their siblings. We propose that the combination of targeted provisioning, flexible levels of provisioning and the dispersed nature of fledglings reduces the benefits of competitive or cooperative begging in this species.

Audrey Delsink, Abi T. Vanak, Sam Ferreira, Rob Slotow, Biologically relevant scales in large mammal management policies, Biological Conservation, Volume 167, November 2013, Pages 116-126, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.07.035.
The African elephant is an important keystone species that may have significant effects on ecosystem structure and eco-tourism revenues. In Kruger National Park (KNP), South Africa, where elephant populations have been increasing, management have adopted a zonation approach, with zones identified for specific and measurable management interventions to control elephant populations, or to reduce conflict with humans. Localised culling is one proposed management intervention. The zones, partly derived from static annual elephant distribution surveys, are intended to encompass only localised effects on elephant within that zone, assuming no effect into adjacent undisturbed zones, or into contiguous neighbouring landholdings outside KNP. We deployed 17 GPS/GSM collars on free-roaming elephant herds within KNP to assess their seasonal home-range use and size and daily movement paths. These temporally robust movement metrics were analyzed against the Park’s elephant management zones, partly derived from sporadic telemetry fixes and static distribution counts. Multiple daily and seasonal spatial shifts by elephant across neighbouring zones, including into adjacent reserves, rendered the principle of exclusive zoning at this management scale incorrect. The KNP management zones and proposed management actions are not biologically relevant to elephant, or appropriate for managing the ecological or human-wildlife impact of elephant, resulting in spatial and temporal scale mismatches. We predict that the intended management actions, specifically culling, and its resultant intended consequences (immigration, reduced vegetation impact and reduced growth due to disturbance) is not localised to the target zone, and, because it is season specific, is at risk of targeting transient non-resident elephant whilst missing resident elephant that have crossed into other zones. This scale mismatch may have a ripple effect outside the target zone, causing serious ecological risks, especially given the documented long-term negative effects of management disturbance on elephant. We further quantify this scale mismatch into four categories based on percentages of the following factors: the proportion of sampled population affected, the seasonal zone occupancy (the proportion of locations per zone per season) and number of zone crossings, and the governance of management units (consistency of management interventions imposed across zones). This generates a prediction of the risk of this exclusive zoning and its consequences. We suggest a new approach, whereby, known elephant intensity of use at local scales is adaptively managed for specific management objectives. However, management must occur within a known and contained zone of influence defined by elephant behaviour derived from resident movement studies, as opposed to broad scale zonation at the population or park level.

Franssen, N. R. and Durst, S. L. (2013), Prey and non-native fish predict the distribution of Colorado pikeminnow (Ptychocheilus lucius) in a south-western river in North America. Ecology of Freshwater Fish. doi: 10.1111/eff.12093
Colorado pikeminnow (Ptychocheilus lucius) has been extirpated from a large portion of its historical range in the Colorado River basin, USA. A repatriation effort via stocking of juvenile P. lucius in the San Juan River, NM, CO and UT has resulted in limited recruitment of individuals into an adult population. Understanding biotic and abiotic factors that limit their persistence in the Colorado River basin will be a critical step in providing for their recovery. To elucidate potential recruitment barriers in the San Juan River, we assessed relationships between the numbers of two age classes of P. lucius and prey, competitors and predators collected at a 1.6 km reach scale between 2003 and 2012. We used an information theoretical approach to rank candidate models testing the relative importance of these biotic conditions in predicting the spatial distribution of P. lucius. We found positive relationships between the numbers of P. lucius ≤200 mm total length (TL) collected and catch per unit effort (CPUE) of native prey among reaches. For P. lucius >200 mm TL (individuals that are likely completely piscivorous), we found positive associations between the numbers of P. lucius collected and CPUE of total prey and CPUE of potential non-native competitors in each reach. Our data suggest size-specific affinities of P. lucius for native and non-native prey as well as the potential for negative interactions between P. lucius and non-native competitors may contribute to limited recruitment of juvenile P. lucius into an adult population in the San Juan River.

Miguel Correia, Jorge Palma, Heather Koldewey, José Pedro Andrade, Can artificial holdfast units work as a habitat restoration tool for long-snouted seahorse (Hippocampus guttulatus Cuvier)?, Journal of Experimental Marine Biology and Ecology, Volume 448, October 2013, Pages 258-264, ISSN 0022-0981, http://dx.doi.org/10.1016/j.jembe.2013.08.001.
The recent decline of the seahorse populations in the Ria Formosa lagoon could indicate the presence of a stressful factor due to habitat loss. Artificial structures have been successfully used as a recovery tool to cope with habitat degradation in many countries but none for this seahorse species (Hippocampus guttulatus). Four different artificial holdfasts (S1–S4) were tested in laboratory for seahorse preference under different conditions and different holdfast densities. Seahorses, both juveniles and adults, preferred the holdfast S4, consisting of a “Codium-like” polyethylene nautical rope, even when submitted to different water flows. Preferred holdfast density was 156 holdfast·m− 2, and most of seahorses were observed grasping at the base of these structures (0–10 cm in height). This study provides preliminary data and promising results on an approach to designing artificial holdfasts for seahorses in low complexity damaged or depleted areas. The use of these structures may contribute to the settlement of seahorse populations, thus broadening their potential habitat as part of a wider restoration strategy.

Maldonado-Ocampo, J.A., López-Fernández, H., Taphorn, D.C., Bernard, C.R., Crampton, W.G.R. & Lovejoy, N.R. (2013). Akawaio penak, a new genus and species of Neotropical electric fish (Gymnotiformes, Hypopomidae) endemic to the upper Mazaruni River in the Guiana Shield. —Zoologica Scripta, 00, 000–000.
Akawaio penak, a new genus and species, is described from the upper Mazaruni River, Guyana. The new species is diagnosed from all other species of Hypopomidae by several anatomical traits. The phylogenetic affinities of the new genus were inferred using data from one nuclear (rag2) and two mitochondrial (COI and cyt b) genes. The phylogenetic analyses indicate that Akawaio is the sister taxon of a clade that includes Brachyhypopomus, Hypopomus, Microsternarchus and Racenisia. These results provide evidence for the phylogenetic composition of Hypopomidae supported by previous molecular studies and support the position of the Steatogenini (Hypopygus + Steatogenys) as the sister group of Rhamphichthys + Gymnorhamphichthys. The description of this new electric knifefish increases the total number of endemic genera and species in the upper Mazaruni, a region that is suffering freshwater habitat degradation as consequence of gold-mining activities.

Zootaxa 3702 (3): 233–246 (27 Aug. 2013)
A new species of Kukri Snake (Oligodon Fitzinger, 1826; Squamata: Colubridae) from the Cat Tien National Park, southern Vietnam

We describe a new species of the genus Oligodon from the lowland forests of Cat Tien National Park, Dong Nai Province,  in southern Vietnam. Oligodon cattienensis sp. nov. is distinguished from the remaining Southeast Asian kukri snakes by  the combination of the following characters: medium-sized, deeply forked hemipenes without spines, 17-17-15 dorsal  scale rows, nasal entire, 2 small postoculars, almost equal in size, 167–178 ventrals, 31–35 subcaudals, 24–35 + 5 large  dark-edged vertebral blotches in combination with a yellow-orange or red vertebral stripe between blotches, head pattern  including ocular band, temporal bands and elongated chevron, ventrals pink or whitish (reddish in juveniles) in life, some  bearing a quadrangular dark blotch on each lateral side, or ventrals being entirely dark. Based on the hemipenial morphology  the new species is assigned to the Oligodon cyclurus species group. A comparison table for all Indochinese Oligodon
is provided.

Zootaxa 3702 (3): 262–272 (27 Aug. 2013)
Caesio xanthalytos, a new species of fusilier (Perciformes: Caesionidae) from the Western Indian Ocean, with records of range extensions for several species of Caesionidae

Caesio xanthalytos, a new species of fusilier, closely related to Caesio caerulaurea Lacepède 1801, is described from  several specimens from various localities on the east coast of Africa, and from southern Madagascar. While very similar in  colour pattern to C. caerulaurea, its lateral line lies within a dominant, composite yellow stripe, whereas in C. caurulaurea  the lateral line lies immediately below the yellow stripe. The two species also differ in the number of lateral-line scales, the  modal number of pectoral-fin rays, in the form of the nuchal scale patch, and genetically. The new species has been observed
to school with C. caerulaurea and with C. varilineata Carpenter 1987. The ranges of several species of Caesio and  Pterocaesio and of Dipterygonotus balteatus and Gymnocaesio gymnoptera are extended to localities on the South African east coast.

Robert M. Inman, Brent L. Brock, Kristine H. Inman, Shawn S. Sartorius, Bryan C. Aber, Brian Giddings, Steven L. Cain, Mark L. Orme, Jay A. Fredrick, Bob J. Oakleaf, Kurt L. Alt, Eric Odell, Guillaume Chapron, Developing priorities for metapopulation conservation at the landscape scale: Wolverines in the Western United States, Biological Conservation, Volume 166, October 2013, Pages 276-286, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.07.010.
Wildlife populations are often influenced by multiple political jurisdictions. This is particularly true for wide-ranging, low-density carnivores whose populations have often contracted and remain threatened, heightening the need for geographically coordinated priorities at the landscape scale. Yet even as modern policies facilitate species recoveries, gaps in knowledge of historical distributions, population capacities, and potential for genetic exchange inhibit development of population-level conservation priorities. Wolverines are an 8–18 kg terrestrial weasel (Mustelidae) that naturally exist at low densities (∼5/1000 km2) in cold, often snow-covered areas. Wolverines were extirpated, or nearly so, from the contiguous United States by 1930. We used a resource selection function to (1) predict habitat suitable for survival, reproduction and dispersal of wolverines across the western US, (2) make a rough estimate of population capacity, and (3) develop conservation priorities at the metapopulation scale. Primary wolverine habitat (survival) existed in island-like fashion across the western US, and we estimated capacity to be 644 wolverines (95% CI = 506–1881). We estimated current population size to be approximately half of capacity. Areas we predicted suitable for male dispersal linked all patches, but some potential core areas appear to be relatively isolated for females. Reintroduction of wolverines to the Southern Rockies and Sierra-Nevadas has the potential to increase population size by >50% and these regions may be robust to climate change. The Central Linkage Region is an area of great importance for metapopulation function, thus warranting collaborative strategies for maintaining high survival rates, high reproductive rates, and dispersal capabilities. Our analysis can help identify dispersal corridors, release locations for reintroductions, and monitoring targets. The process we used can serve as an example for developing collaborative, landscape-scale, conservation priorities for data-sparse metapopulations.

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