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Eagan, MN, United States

Young A.M.,New Mexico State University | Hobson E.A.,New Mexico State University | Lackey L.B.,International Species Information System | Wright T.F.,New Mexico State University
Animal Conservation | Year: 2012

Members of the order Psittaciformes (parrots and cockatoos) are among the most long-lived and endangered avian species. Comprehensive data on lifespan and breeding are critical to setting conservation priorities, parameterizing population viability models, and managing captive and wild populations. To meet these needs, we analyzed 83 212 life-history records of captive birds from the International Species Information System (ISIS) and calculated lifespan and breeding parameters for 260 species of parrots (71% of extant species). Species varied widely in lifespan, with larger species generally living longer than smaller ones. The highest maximum lifespan recorded was 92 years in Cacatua moluccensis, but only 11 other species had a maximum lifespan over 50 years. Our data indicate that while some captive individuals are capable of reaching extraordinary ages, median lifespans are generally shorter than widely assumed, albeit with some increase seen in birds presently held in zoos. Species that lived longer and bred later in life tended to be more threatened according to IUCN classifications. We documented several individuals of multiple species that were able to breed for more than two decades, but the majority of clades examined had much shorter active reproduction periods. Post-breeding periods were surprisingly long and in many cases surpassed the duration of active breeding. Our results demonstrate the value of the ISIS database to estimate life-history data for an at-risk taxon that is difficult to study in the wild, and provide life-history data that is crucial for predictive modeling of future species endangerment and proactively management of captive populations of parrots. © 2011 The Authors. Animal Conservation © 2011 The Zoological Society of London.

Barnes S.A.,White Oak Conservation Center | Andrew Teare J.,International Species Information System | Staaden S.,Jacksonville Zoo and Gardens | Metrione L.,South East Zoo Alliance for Reproduction and Conservation | Penfold L.M.,South East Zoo Alliance for Reproduction and Conservation
General and Comparative Endocrinology | Year: 2016

Basic reproductive information in female jaguars (. Panthera onca) is lacking, thus longitudinal fecal samples from seven females were analyzed via enzyme immunoassay to measure estradiol and progestin metabolites throughout the year. Mean estrus length of 194 estrus periods measured hormonally was 6.5 ± 0.3 d, mean peak fecal estradiol concentration was 138.7 ± 5.7 ng/g; and in one female, estrus resumption occurred approximately 15 d post-partum. Ovulation, as indicted by sustained elevated progestin concentrations (>20 d), was successfully induced one time by treatment with exogenous hormones in one female and by physical vaginal stimulation in two females a combined total of three times. Elevated fecal progestin was observed outside exogenous stimulation on five occasions, suggesting ovulation occurred spontaneously. Mean length of physically induced and spontaneous pseudopregnancies was 24.7 ± 4.2 d and 29.6 ± 2.6 d, respectively, and mean length of pregnancy (n = 2) was 98.0 ± 0.0 d. Mean peak progestin concentration for spontaneous and induced pseudopregnancies, and pregnancy was 7.4 ± 1.4 μg/g, 6.4 ± 1.2 μg/g, and 13.7 ± 1.0 μg/g, respectively. This data suggests jaguars are polyestrous and generally induced ovulators, with a moderate incidence of spontaneous ovulation. Additionally, two protocols to successfully stimulate ovarian activity in jaguars are described. © 2015 Elsevier Inc.

Zerbe P.,University of Zurich | Clauss M.,University of Zurich | Codron D.,University of Zurich | Codron D.,Florisbad Quaternary Research | And 7 more authors.
Biological Reviews | Year: 2012

Many ruminant species show seasonal patterns of reproduction. Causes for this are widely debated, and include adaptations to seasonal availability of resources (with cues either from body condition in more tropical, or from photoperiodism in higher latitude habitats) and/or defence strategies against predators. Conclusions so far are limited to datasets with less than 30 species. Here, we use a dataset on 110 wild ruminant species kept in captivity in temperate-zone zoos to describe their reproductive patterns quantitatively [determining the birth peak breadth (BPB) as the number of days in which 80% of all births occur]; then we link this pattern to various biological characteristics [latitude of origin, mother-young-relationship (hider/follower), proportion of grass in the natural diet (grazer/browser), sexual size dimorphism/mating system], and compare it with reports for free-ranging animals. When comparing taxonomic subgroups, variance in BPB is highly correlated to the minimum, but not the maximum BPB, suggesting that a high BPB (i.e. an aseasonal reproductive pattern) is the plesiomorphic character in ruminants. Globally, latitude of natural origin is highly correlated to the BPB observed in captivity, supporting an overruling impact of photoperiodism on ruminant reproduction. Feeding type has no additional influence; the hider/follower dichotomy, associated with the anti-predator strategy of 'swamping', has additional influence in the subset of African species only. Sexual size dimorphism and mating system are marginally associated with the BPB, potentially indicating a facilitation of polygamy under seasonal conditions. The difference in the calculated Julian date of conception between captive populations and that reported for free-ranging ones corresponds to the one expected if absolute day length was the main trigger in highly seasonal species: calculated day length at the time of conception between free-ranging and captive populations followed a y = x relationship. Only 11 species (all originating from lower latitudes) were considered to change their reproductive pattern distinctively between the wild and captivity, with 10 becoming less seasonal (but not aseasonal) in human care, indicating that seasonality observed in the wild was partly resource-associated. Only one species (Antidorcas marsupialis) became more seasonal in captivity, presumably because resource availability in the wild overrules the innate photoperiodic response. Reproductive seasonality explains additional variance in the body mass-gestation period relationship, with more seasonal species having shorter gestation periods for their body size. We conclude that photoperiodism, and in particular absolute day length, are genetically fixed triggers for reproduction that may be malleable to some extent by body condition, and that plasticity in gestation length is an important facilitator that may partly explain the success of ruminant radiation to high latitudes. Evidence for an anti-predator strategy involving seasonal reproduction is limited to African species. Reproductive seasonality following rainfall patterns may not be an adaptation to give birth in periods of high resource availability but an adaptation to allow conception only at times of good body condition. © 2012 The Authors. Biological Reviews © 2012 Cambridge Philosophical Society.

Levitis D.A.,Max Planck Institute for Demographic Research | Levitis D.A.,University of California at Berkeley | Lackey L.B.,International Species Information System
Methods in Ecology and Evolution | Year: 2011

1.While classical life-history theory does not predict postreproductive life span (PRLS), it has been detected in a great number of taxa, leading to the view that it is a broadly conserved trait and attempts to reconcile theory with these observations. We suggest an alternative: the apparently wide distribution of significant PRLS is an artefact of insufficient methods. 2.PRLS is traditionally measured in units of time between each individual's last parturition and death, after excluding those individuals for whom this interval is short. A mean of this measure is then calculated as a population value. We show this traditional population measure (which we denote PrT) to be inconsistently calculated, inherently biased, strongly correlated with overall longevity, uninformative on the importance of PRLS in a population's life history, unable to use the most commonly available form of relevant data and without a realistic null hypothesis. Using data altered to ensure that the null hypothesis is true, we find a false-positive rate of 0·47 for PrT. 3.We propose an alternative population measure, using life-table methods. Postreproductive representation (PrR) is the proportion of adult years lived which are postreproductive. We briefly derive PrR and discuss its properties. We employ a demographic simulation, based on the null hypothesis of simultaneous and proportional decline in survivorship and fecundity, to produce a null distribution for PrR based on the age-specific rates of a population. 4.In an example analysis, using data on 84 populations of human and nonhuman primates, we demonstrate the ability of PrR to represent the effects of artificial protection from mortality and of humanness on PRLS. PrR is found to be higher for all human populations under a wide range of conditions than for any nonhuman primate in our sample. A strong effect of artificial protection is found, but humans under the most adverse conditions still achieve PrR of >0·3. 5.PrT should not be used as a population measure and should be used as an individual measure only with great caution. The use of PrR as an intuitive, statistically valid and intercomparable population life-history measure is encouraged. © 2011 The Authors. Methods in Ecology and Evolution © 2011 British Ecological Society.

Conde D.A.,University of Southern Denmark | Conde D.A.,Center for Research and Conservation | Colchero F.,University of Southern Denmark | Gusset M.,World Association of Zoos and Aquariums | And 5 more authors.
PLoS ONE | Year: 2013

Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful. © 2013 Conde et al.

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