Development of restoration techniques for Hawaiian thrushes: Collection of wild eggs,artificial incubation,hand‐rearing,captive‐breeding,and re‐introduction to the wild

From 1995 to 1999, two species of endemic Hawaiian thrushes, `Oma`o (Myadestes obscurus) and Puaiohi (M. palmeri), were captive‐reared and re‐introduced into their historic range in Hawai`i by The Peregrine Fund, in collaboration with the U.S. Geological Survey–Biological Resources Division (BRD) and the Hawai`i State Department of Land and Natural Resources. This paper describes the management techniques that were developed (collection of wild eggs, artificial incubation, hand‐rearing, captive propagation, and release) with the non‐endangered surrogate species, the `Oma`o; techniques that are now being used for recovery of the endangered Puaiohi. In 1995 and 1996, 29 viable `Oma`o eggs were collected from the wild. Of 27 chicks hatched, 25 were hand‐reared and released into Pu`u Wa`awa`a Wildlife Reserve. Using the techniques developed for the `Oma`o, a captive propagation and release program was initiated in 1996 to aid the recovery of the endangered Puaiohi. Fifteen viable Puaiohi eggs were collected from the wild (1996–1997) to establish a captive breeding flock to produce birds for re‐introduction. These Puaiohi reproduced for the first time in captivity in 1998 (total Puaiohi chicks reared in captivity 1996–1998 = 41). In 1999, 14 captive‐bred Puaiohi were re‐introduced into the Alaka`i Swamp, Kaua`i. These captive‐bred birds reproduced and fledged seven chicks in the wild after release. This is the first endangered passerine recovery program using this broad spectrum of management techniques (collection of wild eggs, artificial incubation, hand‐rearing, captive‐breeding, and release) in which re‐introduced birds survived and bred in the wild. Long‐term population monitoring will be published separately [BRD, in preparation]. Zoo Biol 19:263–277, 2000. © 2000 Wiley‐Liss, Inc.     

Introducing an innovative semi‐captive environment for the Philippine tarsier (Tarsius syrichta)

In response to demands for research, captive breeding, and tourism, a semi‐captive environment was created for the Philippine tarsiers (Tarsius syrichta) in Corella, Bohol, Philippines. The 7600‐m² enclosure was continuous with the surrounding habitat, and utilized a unique predator control fence design and a lighting system to attract nocturnal insects. During 2 years of observation, the locations of over 500 tarsier sleeping sites were recorded. Tarsiers were found to prefer dense, low‐level vegetation in secondary forests, with perching sites averaging 2 m above the ground. Up to 10 tarsiers were observed within the enclosure at one time, which is a high density compared to densities based on home‐range estimates for wild tarsiers in the vicinity of the study site. In addition, the tarsiers were observed to be more social than previously reported. Zoo Biol 24:101–109, 2005. © 2005 Wiley‐Liss, Inc.     

Corticosterone responses of hand‐reared and parent‐reared grey‐faced petrel chicks (Pterodroma macroptera gouldi)

Hand‐reared grey‐faced petrel (Pterodroma macroptera gouldi) chicks (Order Procellariformes) that were subjected to a standardised blood sampling protocol immediately before they fledged showed a reduced corticosterone response compared to parent‐raised chicks. Serum corticosterone concentrations were lower in hand‐reared than parent‐reared birds 30 and 60 min after handling was initiated (21.5±6.7 vs. 105.4±7.4 ng/ml at 30 min, and 11.3±3.6 vs. 93.8±11.4 ng/ml at 60 min, respectively). The total integrated corticosterone response and the response corrected for initial corticosterone concentrations were similarly lower in hand‐reared than parent‐reared birds (927±489 vs. 4639±1924 ng/ml.min, and 529±352 vs. 4110±1896 ng/ml.min, respectively). Habituation to handling associated with hand‐rearing, which is expressed as a subdued corticostrone response, is likely to reduce the physiological stress associated with the translocation and reintroduction of these birds. However, the longer‐term consequences of this attenuated response remain unclear. Zoo Biol 0:1–8, 2005. © 2005 Wiley‐Liss, Inc.     

Taming parent‐reared orange‐winged Amazon parrots by neonatal handling

Tameness in parrots is often achieved by artificial rearing, in which chicks are typically removed from parents, fed a liquified or semi‐liquified diet by oral gavage and maintained in thermally controlled brooders until they are grown. As an alternate means of rearing birds, we tested whether occasional neonatal human handling of parent‐reared chicks might produce tameness while reducing the risk of sexual imprinting on humans. Orange‐winged Amazon chicks (Amazona amazonica) were incubated and hatched by wild‐caught parents, then were temporarily removed from the nest box, and handled at various times during the nestling period. In Trial 1, handled chicks (n = 6) were handled from days 10 to 39 of age for 10–20 min/day and from 40 days to fledging (days 56–/57) for 20–30 min/day. Nonhandled chicks (n = 4) were handled only to record body weight and provide medication, as needed. After fledging, chicks were evaluated for tameness, e.g., by their willingness to approach the handler, perch on a finger, be touched on the head, and by their respiratory rate in the presence of the handler. Handled birds differed significantly in all indices of tameness. In Trial 2, handled chicks were handled for 30 min, four times/week either from days 15 to 36 (n = 3) or 35 to 56 (n = 3); results were similar to Trial 1. Chicks handled later tended to be slightly tamer than those handled earlier. In both trials, the amount of time that handled chicks were in contact with humans was less than 2% of the time they spent with conspecifics. It is therefore unlikely that these chicks imprinted either filially or sexually on humans, although this has not been experimentally tested. While continued handling is likely necessary to maintain tameness, these results support the concept that neonatal handling of parent‐raised parrots provides a low‐labor and low‐technology alternative to artificial rearing as a means of initially taming birds, thereby improving their adaptation to life in captivity. Zoo Biol 18:177–187, 1999. © 1999 Wiley‐Liss, Inc.     

Long‐term transportation,by road and air,of Devil‐ray (Mobula mobular), Meagre (Argyrosomus regius), and Ocean Sunfish (Mola mola)

Between September 2006 and April 2007 the authors transported one 0.9 m wingspan Mobula mobular from Olhão (South of Portugal) to Valencia (East of Spain), 12 ∼1.0 m long Argyrosomus regius to Tarragona (Northeast of Spain) and four ∼0.4 m long Mola mola to Atlanta (GA, USA). These journeys had a total “water to water” duration of 17, 22 and 33 hr, respectively. The first two transports were conducted by road whereas the third involved a combination of road and air travel. Water quality parameters—specifically dissolved oxygen, temperature, pH and ammonia—were monitored continuously throughout the duration of the trips and were maintained at optimum levels through the use of battery‐powered filtration and chemical supplements. All animals arrived alive and well at their destinations. This paper reports on the specific transport regime adopted in each case and provides some insight for potential improvements in future similar transports. Zoo Biol 27:234–250, 2008. © 2008 Wiley‐Liss, Inc.     

Prevalence of gastrointestinal parasites in captive non‐human primates of twenty‐four zoological gardens in China

Captive primates are susceptible to gastrointestinal (GIT) parasitic infections, which are often zoonotic and can contribute to morbidity and mortality. Fecal samples were examined by the means of direct smear, fecal flotation, fecal sedimentation, and fecal cultures. Of 26.51% (317/1196) of the captive primates were diagnosed gastrointestinal parasitic infections. Trichuris spp. were the most predominant in the primates, while Entamoeba spp. were the most prevalent in Old World monkeys (P < 0.05). These preliminary data will improve the management of captive primates and the safety of animal keepers and visitors.     

Survival rates of captive‐bred Asian Houbara Chlamydotis macqueenii in a hunted migratory population

Asian Houbara Chlamydotis macqueenii numbers are declining as a result of unsustainable levels of hunting and poaching, with the main conservation response being population reinforcement through the release of captive‐bred birds. We assessed the contribution of captive breeding to the species’ conservation by examining the fates of 65 captive‐bred birds fitted with satellite transmitters and released during spring (March–May) and autumn (August) into breeding habitat in Uzbekistan. Of the released birds, 58.5% survived to October, the month favoured by Emirati hunters in Uzbekistan, but only 10.8% of those released survived the winter to return as subadults next spring. To mitigate and compensate for the loss of wild adults to hunting, the number of released birds needs to be an order of magnitude higher than hunting quotas (with a release of between 1640 and 1920 required for a hypothetical quota of 200), indicating that releases may be costly and do not remove the need for a biologically determined sustainable hunting quota.     

netview p: a network visualization tool to unravel complex population structure using genome‐wide SNPs

Network‐based approaches are emerging as valuable tools for the analysis of complex genetic structure in wild and captive populations. netview p combines data quality control with the construction of population networks through mutual k‐nearest neighbours thresholds applied to genome‐wide SNPs. The program is cross‐platform compatible, open‐source and efficiently operates on data ranging from hundreds to hundreds of thousands of SNPs. The pipeline was used for the analysis of pedigree data from simulated (n = 750, SNPs = 1279) and captive silver‐lipped pearl oysters (n = 415, SNPs = 1107), wild populations of the European hake from the Atlantic and Mediterranean (n = 834, SNPs = 380) and grey wolves from North America (n = 239, SNPs = 78 255). The population networks effectively visualize large‐ and fine‐scale genetic structure within and between populations, including family‐level structure and relationships. netview p comprises a network‐based addition to other population analysis tools and provides user‐friendly access to a complex network analysis pipeline through implementation in python .     

Factors affecting reproduction in zoo‐housed geoffroy's tamarins(Saguinus geoffroyi)

The captive population of Geoffroy's tamarins (Saguinus geoffroyi) has suffered a severe decline over the past 10 years. This population decline is attributed not to a failure to produce offspring, but rather to a failure to successfully rear offspring. To date, no studies have quantitatively examined the behaviors and hormones of this tamarin species in captivity. Therefore, this study was conducted to determine whether there were any discernable factors that could be correlated with failure to rear offspring in S. geoffroyi. Fifteen adult Geoffroy's tamarins (GTs) at the Cleveland Metroparks Zoo (CMZ) were observed by means of instantaneous sampling on a focal animal. In addition, all instances of social behaviors were recorded. A factorial arrangement of treatments was used, as animals were divided between a colony‐housing situation and a non‐colony situation with hand‐reared and mother‐reared animals in both treatments. Repeated‐measures analysis of variance (ANOVA) showed no interactions between the treatments, and no differences between rearing histories for the behaviors studied. However, animals housed in a colony setting exhibited higher levels of aggressive behaviors and lower activity levels compared to those in a non‐colony setting. There also was a trend for colony‐housed animals to huddle, scent‐mark, and exhibit sexual behaviors more often than non‐colony animals. First‐morning‐void urine samples were collected once per week, and assays for E₁C and PdG indicated that reproduction was not being suppressed. ANOVA conducted on samples assayed for excreted cortisol showed no differences in mean cortisol concentration by rearing histories or housing conditions. While these physiological indicators reveal no signs of stress, high levels of aggressive and territorial behaviors indicate social unrest in the colony‐housed condition, which may be contributing to the poor reproductive success of those individuals. Zoo Biol 22:545–559, 2003. © 2003 Wiley‐Liss, Inc.     

Predicting release success of captive‐reared loggerhead shrikes (Lanius ludovicianus) using pre‐release behavior

We assessed whether behavioral markers could be used to evaluate pair compatibility and predict pair bond success of captive‐reared San Clemente loggerhead shrikes (Lanius ludovicianus mearnsi) released into the wild. Potential breeding pairs of shrikes were introduced at the Zoological Society of San Diego's captive‐breeding facility and then moved to release cages located in suitable but unoccupied habitat. Courting pairs were affected negatively by the disturbance of translocation to a new location and generally needed a few days to reinitiate pair bonding in the release enclosures. We separated and returned pairs to captivity when intra‐pair aggression or cessation of all courtship behavior occurred; all other pairs were released into the wild. The rate of nest approaches was the best marker to predict a successful release into the wild (i.e., pairs that remained near the release site and attempted to breed). Additionally, all experienced breeding pairs (i.e., pairs with males and females with prior captive breeding experience) exhibiting nesting behavior were successful, although previous experience alone does not ensure post‐release breeding. Results from this study indicate the importance of assessing behaviors of individuals paired for population augmentation. In using behavioral cues, identifying pairs with a low probability of success is possible, and replacing these pairs with individuals that have a higher likelihood of post‐release success can occur. This strategy will be important to efficiently restore imperiled populations of endangered species while working within temporal and financial constraints. Zoo Biol 0:1–12, 2005. © 2005 Wiley‐Liss, Inc.     

Acid‐insoluble ash as a measure of dry matter digestibility in captive African elephants (Loxodonta africana)

There are limited data on the diet dry matter digestibility (DMD) of captive African elephants. Although the total fecal collection method is the standard for determining DMD, it is labor‐intensive, time‐consuming, and expensive. The acid‐insoluble ash (AIA) marker technique has been used successfully to determine DMD in ruminants and monogastrics. The objective of this study was to assess how accurately the AIA marker technique could estimate the DMD of captive African elephants (Loxodonta africana). Three mature male African elephants at Disney's Animal Kingdom in Florida were used in this study. The animals were offered a Bermuda grass hay‐based ration, and the total dry matter intake (DMI) and total fecal output were measured daily over a 7‐day period to determine the total collection DMD. The feed ingredients and fecal samples were also analyzed for AIA. Although there were differences (P<0.05) in total DMI and total fecal outputs, the DMD values did not (P>0.05) differ (35.1±0.72 vs. 37.1±0.72 for total collection and AIA, respectively). There was a linear (y=0.9461x; R²=0.74) relationship between the total collection and AIA marker technique DMD values. These results suggest that AIA can be used to accurately estimate the DMD of captive African elephants. Zoo Biol 0:1–5, 2005. © 2005 Wiley‐Liss, Inc.     

Differences in fecal particle size between free‐ranging and captive individuals of two browser species

Data from captive animals indicated that browsing (BR) ruminants have larger fecal particles—indicative of lesser chewing efficiency—than grazers (GR). To answer whether this reflects fundamental differences between the animal groups, or different reactions of basically similar organisms to diets fed in captivity, we compared mean fecal particle size (MPS) in a GR and a BR ruminant (aurox Bos primigenius taurus, giraffe Giraffa camelopardalis) and a GR and a BR hindgut fermenter (Przewalski's horse Equus ferus przewalskii, lowland tapir Tapirus terrestris), both from captivity and from the wild. As would be expected owing to a proportion of finely ground, pelleted feeds in captive diets, MPS was smaller in captive than free‐ranging GR. In contrast, MPS was drastically higher in captive than in free‐ranging BR of either digestion type. Thus, the difference in MPS between GR and BR was much more pronounced among captive than free‐ranging animals. The results indicate that BR teeth have adapted to their natural diet so that in the wild, they achieve a particle size reduction similar to that of GR. However, although GR teeth seem equally adapted to food ingested in captivity, the BR teeth seem less well suited to efficiently chew captive diets. In the case of ruminants, less efficient particle size reduction could contribute to potential clinical problems like “rumen blockage” and bezoar formation. Comparisons of MPS between free‐ranging and captive animals might offer indications for the physical suitability of zoo diets. Zoo Biol 27:70–77, 2008. © 2007 Wiley‐Liss, Inc.     

Captive Husbandry and Socialization of the Red‐Billed Chough (Pyrrhocorax pyrrhocorax)

Since the 1970s, Paradise Park Wildlife Sanctuary in Cornwall, United Kingdom, has built up a captive flock of red‐billed choughs Pyrrhocorax pyrrhocorax and over 30 years has developed successful methods of keeping, breeding, and appropriately socializing them in captivity. A total of 77 nests reached the egg stage with 27 nests producing at least one young and 48 young fledging in total. Several components are important in achieving successful breeding and socialization. Provision of live food, especially ant's eggs and small mealworms and crickets, in the first days after hatching is essential, improving the condition of adults and survival of nestlings. Situating aviaries in quiet areas, away from public view, is important. Socialization in family groups during the winter months and allowing choughs to choose partners induces better compatibility. Introduction of nest cameras greatly improved young survival through early identification of health problems enabling treatment of young between hatching and 10‐days old, when mortality is otherwise highest, and enabling precautionary medication shortly after hatching. We show that clutch size increases significantly with female age and that direct intervention such as artificial egg incubation and hand rearing can be successful and worthwhile, but its requirement is reduced by closer monitoring. Red‐billed choughs provide a good model species to further develop captive management and release techniques that can then be applied to critically endangered species that show similar social and long‐learning behaviors. Captive breeding programs can play an important role in such work through provision of suitable birds and supporting avicultural expertise. Zoo Biol. 31:725‐735, 2012. © 2012 Wiley Periodicals, Inc.     

Sexual recruitment of the corals Favia fragum and Agaricia humilis in a 30‐m3 exhibit aquarium: species‐specific limitations and implications on reproductive ecology

We studied the recruitment of the Caribbean reef building corals Favia fragum (F. fragum) and Agaricia humilis(A. humilis) in captivity. Thirty colonies of each species collected in Curaçao, Netherlands Antilles, reproduced sexually during a temporary stay in a 30‐m³ closed system from November 2001–January 2002. Twelve months later, the F1 generation of F. fragum started reproducing and formed an F2 generation. No reproduction of the F1 recruits of A. humilis was observed. Two years after the introduction of the field colonies, sexual recruits of both species were assessed using two different methods: recruits were estimated using quadrats (quadrat sampling method) and the total number of recruits was counted by creating a map of the artificial rock work divided in distinct areas (area census method). Recruitment rates of F. fragum were highest for the F2 generation on horizontal surfaces (area census method: 137.9±191.7 recruits m^?2; quadrat sampling method: 272.0±254.8 recruits m^?2; mean±SD) and were overall lowest for the F1 generation on overhanging areas of the tank (area census method: 3.8±4.0 recruits m^?2; quadrat sampling method: 4.0±6.1 recruits m^?2; mean±SD recruits m^?2). The populations of both species showed similar patterns independent of the applied assessment method with highest densities on horizontal surfaces followed by vertical surfaces and lowest densities on overhanging surfaces; however, both methods showed conflicting results when the influence of the surface orientation on the population densities was statistically analyzed. The maximum density of A. humilis (1.4±2.7 recruits m^?2 on horizontal surfaces) was much lower than the maximum density of the F1 generation of F. fragum (24.7±18.3 recruits m^?2). Colony sizes of recruits within each population (F. fragum F1: 3.12±0.98 cm, F2: 0.83±0.41 cm; A. humilis F1: 3.79±1.35 cm; maximum diameter±SD) did not differ between different orientations (horizontal vs. vertical vs. overhanging). Calculated growth rates in the aquarium reflected those observed for F. fragum in the field, whereas A. humilis showed slower growth in the aquarium than in the field. Factors such as competition, sedimentation, and predation, that generally reduce in situ recruitment may be excluded in captivity resulting in far higher recruitment rates. This study confirms that aquarium exhibits can serve as a comparative model to study the ecology of corals under semi‐controlled conditions. Zoo Biol 0:1–17, 2007. © 2007 Wiley‐Liss, Inc.     

Suppression of ovulation in Nile Hippopotamus (Hippopotamus amphibious) using melengestrol acetate‐treated feed or high dose Depo‐Provera injection

Analysis of fecal progestogen profiles during Depo‐Provera injection (1,200 mg; DEPO, Pfizer Inc., New York, NY), melengestrol acetate (MGA) in feed (2 or 3 mg/head/day), and a combination treatment (DEPO+MGA) are presented for nine captive female Nile hippos housed at Disney's Animal Kingdom in Florida. All tested treatments reduced fecal progestogen elevations successfully to durations consistent with prevention of ovulation for a portion of the treatment period. Percentage of treatment months with suppression of luteal phases indicative of ovulation was maximal for high‐dose MGA (91.7±13.9%) and DEPO+MGA (91.7±20.4%), followed by DEPO injection alone (69.2±13.9%) and low‐dose MGA (57.6±33.2%). Both 1,200 mg DEPO and low‐dose MGA (2.0 mg/day) treatments were insufficient to prevent an apparent seasonal breakthrough of ovarian activity from June–August 2002. Although luteal phases were observed, no females conceived during those months. Overall, in 133.5 treatment months with females housed with an adult male, one female conceived during the transition period between treatments. After cessation of contraceptive treatment, average latency to first normal ovarian cycle was 80.6±19.5 days (range = 22–179 days). Up to 12 months post‐treatment, however, successive cycles were often irregular with evidence of short periods of anovulation and shortened luteal phases in all females monitored. In conclusion, high dose and combination treatments were most successful in preventing progestogen increases indicative of ovulation in hippos. Zoo Biol 26:259–274, 2007. © 2007 Wiley‐Liss, Inc.