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Zoo-based (ex situ) conservation breeding programs provide invaluable opportunities to uncover enigmatic behaviors and traits of focal species under managed care, which can support research and conservation management efforts. A suite of factors and a limited range have yielded population declines in the threatened narrow-headed gartersnake (Thamnophis rufipunctatus). Better understanding its cryptic ecology and life history (e.g., reproductive ecology) offers conservation benefits. We analyzed data on courtship behavior, parity and litter size, offspring size, and neonatal growth from an ex situ T. rufipunctatus population at the Phoenix Zoo from 2009 to 2018. Courtship behavior and parturition phenology are likely linked with the North American monsoon season, yet the courtship window may be wider than realized. We document the first instances of interannual iteroparity and multigenerational rearing of successful breeders at the ex situ level. Litter sizes varied but were relative to maternal body mass, suggesting that fecundity may be driven by intrinsic condition (e.g., age and size) of breeding females. Mean offspring body masses were equivalent between sexes, and neonate growth trends were quadratic during their first 9 months. Sexual dimorphism became apparent around 4-5 months age. Much of these data are novel for T. rufipunctatus and provide insight into their reproductive ecology. Phenology of reproductive ecology and body size metrics can guide field surveillance, age estimations, and population ecology monitoring, as well as inform ex situ adaptive management practices. Strategies spanning the ex situ-in situ spectrum are applicable to other imperiled taxa to better inform conservation management decisions.

Predators directly impact prey populations through lethal encounters, but understanding nonlethal, indirect effects is also critical because foraging animals often face trade-offs between predator avoidance and energy intake. Quantifying these indirect effects can be difficult even when it is possible to monitor individuals that regularly interact. Our goal was to understand how movement and resource selection of a predator (wolves; Canis lupus) influence the movement behavior of a prey species (moose; Alces alces). We tested whether moose avoided areas with high predicted wolf resource use in two study areas with differing prey compositions, whether avoidance patterns varied seasonally, and whether daily activity budgets of moose and wolves aligned temporally. We deployed GPS collars on both species at two sites in northern Minnesota. We created seasonal resource selection functions (RSF) for wolves and modeled the relationship between moose first-passage time (FPT), a method that discerns alterations in movement rates, and wolf RSF values. Larger FPT values suggest rest/foraging, whereas shorter FPT values indicate travel/fleeing. We found that the movements of moose and wolves peaked at similar times of day in both study areas. Moose FPTs were 45% lower in areas most selected for by wolves relative to those avoided. The relationship between wolf RSF and moose FPT was nonlinear and varied seasonally. Differences in FPT between low and high RSF values were greatest in winter (-82.1%) and spring (-57.6%) in northeastern Minnesota and similar for all seasons in the Voyageurs National Park ecosystem. In northeastern Minnesota, where moose comprise a larger percentage of wolf diet, the relationship between moose FPT and wolf RSF was more pronounced (ave. across seasons: -60.1%) than the Voyageurs National Park ecosystem (-30.4%). These findings highlight the role wolves can play in determining moose behavior, whereby moose spend less time in areas with higher predicted likelihood of wolf resource selection.

Ungulates that are adapted to cold climates may use bed sites as thermal refuges during summer. At the southern edge of their distribution moose Alces alces often encounter ambient summer temperatures above their upper critical temperature. Summer is also when moose increase food consumption and metabolism, which increases heat generation that must typically be lost at bed sites. To determine if moose use bed sites that enable heat loss when temperatures are hot, we randomly sampled bed sites of moose from across the entire range of ambient summer temperatures. We calculated kernel density estimates for each day and night using GPS locations collected each 20 min for an entire summer to identify bed sites. Kernel density estimates identified bed sites accurately. During the day, moose bedded under lowland forest canopies where substrates had high water content. At night, bed sites were in openings which are associated with greater browse availability and net heat loss. Lowland forests interspersed with op...

Populations inhabiting the bioclimatic edges of a species’ geographic range face an increasing amount of stress from alterations to their environment associated with climate change. Moose Alces alces are large-bodied ungulates that are sensitive to heat stress and have exhibited population declines and range contractions along their southern geographic extent. Using a hidden Markov model to analyze movement and accelerometer data, we assigned behaviors (rest, forage, or travel) to all locations of global positioning system-collared moose (n = 13, moose-years = 19) living near the southern edge of the species’ range in and around Voyageurs National Park, MN, USA. We assessed how moose behavior changed relative to weather, landscape, and the presence of predators. Moose significantly reduced travel and increased resting behaviors at ambient temperatures as low as 15 °C and 24 °C during the spring and summer, respectively. In general, moose behavior changed seasonally in association with distance to lakes and ponds. Moose used wetlands for travel throughout the year, rested in conifer forests, and foraged in shrublands. The influence of wolves Canis lupus varied among individual moose and season, but the largest influence was a reduction in travel during spring when near a wolf home range core, primarily by pregnant females. Our analysis goes beyond habitat selection to capture how moose alter their activities based on their environment. Our findings, along with climate change forecasts, suggest that moose in this area will be required to further alter their activity patterns and space use in order to find sufficient forage and avoid heat stress.

Intergroup conflict occurs in many social species and involves potentially complex motivations and interactions. To understand its complexity in wild animals more fully, a comprehensive investigative approach is needed, in which the multiple resource values and measures of fighting ability that potentially influence intergroup contests are simultaneously considered and controlled for. This study uses long-term data on eight neighbouring groups of folivorous black and white colobus monkeys, Colobus guereza (‘guerezas’) in Kibale National Park, Uganda, to investigate the factors influencing intergroup conflict. Adult males were the main participants in intergroup aggression. Of the three resource values investigated, food value had the most unambiguous positive effect on the tendency for males to initiate high-level intergroup aggression and for groups to win. Mate value positively influenced male initiation of high-level intergroup aggression, but not more so for the group that contained high-value mates. The presence of young infants had no obvious effects. Unlike in many other species, males were more likely to initiate intergroup aggression if their groups were smaller and contained fewer adult males than opposing groups. Groups with fewer but larger adult males, and to some extent, smaller groups, were more likely to win encounters. Moreover, the relative number of adult males/group largely affected the degree to which some other factors influenced male initiation of aggression and contest outcome. These findings reveal that a complex interplay between multiple resource values and multiple fighting ability measures can simultaneously influence initiation of and success in intergroup conflict.

Analyses of plant DNA in feces provides a promising, yet largely unexplored, means of documenting the diets of elusive primates. Here we demonstrate the promise and pitfalls of this approach using DNA extracted from fecal samples of wild western gorillas (Gorilla gorilla) and black and white colobus monkeys (Colobus guereza). From these DNA extracts we amplified, cloned, and sequenced small segments of chloroplast DNA (part of the rbcL gene) and plant nuclear DNA (ITS-2). The obtained sequences were compared to sequences generated from known plant samples and to those in GenBank to identify plant taxa in the feces. With further optimization, this method could provide a basic evaluation of minimum primate dietary diversity even when knowledge of local flora is limited. This approach may find application in studies characterizing the diets of poorly-known, unhabituated primate species or assaying consumer-resource relationships in an ecosystem.

Abstract Intergroup aggression is relatively common in many primate species and its functions have long been debated and incorporated as important parts of primate socioecological models. Recent studies have improved upon previous research by empirically testing the potential mate, food/resource and infant defence functions of intergroup aggression. I raise three main issues regarding the predictions and methods that have been used and make suggestions that should improve future studies. First, I address what constitutes evidence of defence and suggest that encounter rates and contexts should generally not be used to help test mate, resource and infant defence hypotheses. Secondly, I address the problem of disentangling mate, resource and infant defence hypotheses and suggest that because they are not mutually exclusive and potentially confound one another, tests of one hypothesis should adequately control for other possible functions, preferably using multiple logistic regression. Lastly, I discuss the importance of examining intergroup aggression using a cost-benefit approach and suggest that measures should be taken to control for species-specific measures of fighting ability, and/or other potential costs or influential factors that might influence participation in intergroup aggression, including groups' identities. For the latter two issues, I provide simulations that illustrate the methodologies I suggest and the potential effects of employing them, relative to previously employed tests.

In theory, between-group contest (BGC) competition for food can greatly influence female social relationships and reproductive success in primates, but few studies have investigated whether such effects occur and, if so, under what ecological conditions. There is evidence that adult male black and white colobus monkeys (Colobus guereza, “guerezas”) defend the food their mates need against other groups, suggesting that BGC competition is important in this species. Using data on feeding, ranging, vegetation patterns, and intergroup encounters between six neighboring guereza groups, I provide evidence that the highly folivorous guerezas at Kanyawara, Kibale National Park, Uganda, engaged in BGC competition over unevenly dispersed, relatively high-quality feeding areas or “core areas”. Intergroup aggression was common, and groups’ home ranges overlapped. Groups were more likely to initiate high-level aggression if they encountered another group within or near their core area, and groups that initiated and won encounters often fed in the same areas in which losing groups had fed. Guerezas fed selectively on species with contagious (clumped) distributions and concentrated their feeding efforts in areas of the forest that contained the most food (core areas). Groups could be ranked in a linear dominance hierarchy, and group rank number was inversely related to the quantity and quality of food in groups’ core areas. This study not only provides good evidence that BGC competition occurs in primates but it also reinforces the idea that folivore food resources may be worth defending.

Formant dispersion, the average spacing, in Hz, between the resonant frequencies of a vocalization, has been predicted to provide honest information about signaler body size. Previous descriptions of black and white colobus monkey (Colobus guereza, ‘‘guereza’’) roars, however, suggest a formant dispersion that is far lower than expected for an animal its size, and could effectively exaggerate its body size. Nonetheless, recent research on red deer shows that even when the formant positions of vocalizations effectively exaggerate body size, they may still provide honest cues within a species. We investigate whether the frequency bands observed in the spectrograms of guereza roars represent formants, and whether roar formant dispersion and/or individual formants provide honest information about body size (specifically, body mass) relative to conspecifics, although perhaps not relative to other species. We document coordinated vertical movements in the frequency bands of guereza roars and show that these bands move independently of fundamental frequency, indicating that they represent formants. We show, for captive adult male guerezas, that signaler body mass significantly predicts roar formant dispersion, even for randomly selected calls. Body mass also predicts formants 2 and 3, but the relationships are not as strong as with formant dispersion. Our roar formant dispersion calculations predict a vocal tract length of approx. 29 cm, but anatomically determined guereza vocal tract length is much smaller: approx. 7–8 cm. Videotaped roars revealed no laryngeal movement during roars, but rather inflation of the subhyoid air sac. We measured the volume of this air sac (approx. 10 cm 3 ) and speculate that it may function in roars to exaggerate body size, relative to other species.

To test hypotheses about loud call function, researchers have typically used playback experiments and/or analyzed the contexts in which calls are produced. Analyzing the variation within and among individuals' loud calls may also provide insights about their function, including advertisement of callers' fighting abilities. This study tests whether some male black and white colobus monkeys (Colobus guereza, 'guerezas') indicate their willingness to defend access to important feeding areas and/or mates by increasing the number of roars they produce/chorus, their roar lengths, and/or overall roaring effort. It also tests whether mean values for these roaring variables indicate male fighting ability. My assistants and I followed six guereza groups for three months each at Kanyawara, Kibale National Park, Uganda. I recorded males' morning chorus roars and used data on roars, intergroup aggression, feeding, and proximity of females to ovulation to test hypotheses about roaring variation. I show that males were the main participants in intergroup aggression, the six study groups can be ranked in a linear dominance hierarchy, and group rank (effectively male rank) predicts and varies positively with how long males roar, as well as overall roaring effort. I provide evidence that some males roar longer when their groups' females are in close proximity to presumptive ovulation. There was relatively little evidence that males roar more when near important feeding areas. Males in higher and lower ranking groups may have different roaring strategies in the presence of important resources, but further studies are needed to fully test this idea. While this study may not provide strong evidence for either a direct mate or food defense function of roars, it shows that roars may advertise a male's ability to defend mates and/or food.

Many studies in molecular ecology rely upon the genotyping of large numbers of low-quantity DNA extracts derived from noninvasive or museum specimens. To overcome low amplification success rates and avoid genotyping errors such as allelic dropout and false alleles, multiple polymerase chain reaction (PCR) replicates for each sample are typically used. Recently, two-step multiplex procedures have been introduced which drastically increase the success rate and efficiency of genotyping. However, controversy still exists concerning the amount of replication needed for suitable control of error. Here we describe the use of a two-step multiplex PCR procedure that allows rapid genotyping using at least 19 different microsatellite loci. We applied this approach to quantified amounts of noninvasive DNAs from western chimpanzee, western gorilla, mountain gorilla and black and white colobus faecal samples, as well as to DNA from ~100-year-old gorilla teeth from museums. Analysis of over 45 000 PCRs revealed average success rates of > 90% using faecal DNAs and 74% using museum specimen DNAs. Average allelic dropout rates were substantially reduced compared to those obtained using conventional singleplex PCR protocols, and reliable genotyping using low (

Complex sex-biased dispersal patterns often characterize social-group-living species and may ultimately drive patterns of cooperation and competition within and among groups. This study investigates whether observational data or genetic data alone can elucidate the potentially complex dispersal patterns of social-group-living black and white colobus monkeys (Colobus guereza, "guerezas"), or whether combining both data types provides novel insights. We employed long-term observation of eight neighbouring guereza groups in Kibale National Park, Uganda, as well as microsatellite genotyping of these and two other neighbouring groups. We created a statistical model to examine the observational data and used dyadic relatedness values within and among groups to analyse the genetic data. Analyses of observational and genetic data both supported the conclusion that males typically disperse from their natal groups and often transfer into nearby groups and probably beyond. Both data types also supported the conclusion that females are more philopatric than males but provided somewhat conflicting evidence about the extent of female philopatry. Observational data suggested that female dispersal is rare or nonexistent and transfers into neighbouring groups do not occur, but genetic data revealed numerous pairs of closely related adult females among neighbouring groups. Only by combining both data types were we able to understand the complexity of sex-biased dispersal patterns in guerezas and the processes that could explain our seemingly conflicting results. We suggest that the data are compatible with a scenario of group dissolution prior to the start of this study, followed by female transfers into different neighbouring groups.

Black and white colobus monkeys (Colobus guereza, “guerezas”) show no external signs of estrus, and little is known about their mating behavior or reproductive endocrinology. To learn more about the life history characteristics and mating system of guerezas, we documented the mating behavior and ovarian hormone profiles of 10 cycling, lactating, and pregnant females in a wild population. We studied six groups of guerezas in Kibale National Park, Uganda, and collected ad libitum data on their mating behavior. We collected urine samples every 1.9±0.2 days from potentially fertile females and quantified conjugated urinary estrogen (E1S) and progesterone (PdG) metabolites using enzyme immunoassay (EIA). Females solicited 50.5% of copulations, and most copulations occurred during the interval starting 5 days before presumptive ovulation and ending 2–3 days later, with the highest copulatory levels occurring close to ovulation. We show that the median ovarian cycle length is 24 days, the median gestation length is ∼158 days, the length of lactational amenorrhea is at least 7–8 months, and the median interbirth interval for females with surviving infants is ∼22 months. We also document overlap between females' receptive periods in one-male, two- to three-female groups, which may mean that male transfer into such groups is potentially profitable. Am. J. Primatol. 68:383–396, 2006.© 2006 Wiley-Liss, Inc.

Infanticide has been observed in several colobines, but only one infanticide has previously been documented for black and white colobus monkeys (Colobus guereza). This report describes an infanticide observed in Kibale National Park, Uganda, in the summer of 2001. An adult male from a neighboring group attacked and killed a young infant whose mother subsequently remained in her own group and was observed mating 10 days later. She engaged in two mating periods of several days each, separated by approximately 1 month, during which she copulated frequently with the dominant male within her group. Urinary estrogen (EC) and progesterone metabolite (PdG) excretion patterns demonstrated that the female resumed ovarian cycling soon after the infanticide. Because the infanticidal male did not attempt to mate with the victim's mother, his actions were not consistent with the predictions of the sexual-selection hypothesis. We speculate that infanticide associated with intergroup aggression may help secure access to high-quality resources for the infanticidal male's group.