Price E.C.,Durrell Wildlife Conservation Trust |
Wormell D.,Durrell Wildlife Conservation Trust |
Brayshaw M.,Durrell Wildlife Conservation Trust |
Furrer S.,Zoo Zurich |
And 2 more authors.
International Zoo Yearbook | Year: 2012
This paper describes the management techniques developed over 20 years of experience with free-ranging groups of callitrichids at Durrell Wildlife Park (formerly Jersey Zoo), UK, with an additional 12 years of information from Zürich Zoo, Switzerland. Seventeen groups of eight different species have been released in woodland areas at Durrell, and two groups at Zürich. Release periods ranged from 2 weeks to 14 years. The evolution of release protocols is described, along with brief descriptions of problems that have occurred. The advantages and problems of maintaining callitrichids in free-ranging environments are discussed. © 2012 The Authors. International Zoo Yearbook © 2012 The Zoological Society of London.
Burivalova Z.,ETH Zurich |
Burivalova Z.,Universitatstrasse 16 |
Bauert M.R.,Zoo Zurich |
Hassold S.,ETH Zurich |
And 2 more authors.
Biotropica | Year: 2015
A global data set on forest cover change was recently published and made freely available for use (Hansen et al. 2013. Science 342: 850-853). Although this data set has been criticized for inaccuracies in distinguishing vegetation types at the local scale, it remains a valuable source of forest cover information for areas where local data is severely lacking. Masoala National Park, in northeastern Madagascar, is an example of a region for which very little spatially explicit forest cover information is available. Yet, this extremely diverse tropical humid forest is undergoing a dramatic rate of forest degradation and deforestation through illegal selective logging of rosewood and ebony, slash-and-burn agriculture, and damage due to cyclones. All of these processes result in relatively diffuse and small-scale changes in forest cover. In this paper, we examine to what extent Hansen et al.'s global forest change data set captures forest loss within Masoala National Park by comparing its performance to a locally calibrated, object-oriented classification approach. We verify both types of classification with substantial ground truthing. We find that both the global and local classifications perform reasonably well in detecting small-scale slash-and-burn agriculture, but neither performs adequately in detecting selective logging. We conclude that since the use of the global forest change data set requires very little technical and financial investment, and performs almost as well as the more resource-demanding, locally calibrated classification, it may be advantageous to use the global forest change data set even for local conservation purposes. © 2015 The Association for Tropical Biology and Conservation.
Karanewsky C.J.,Stanford University |
Karanewsky C.J.,Center ValBio |
Bauert M.R.,Zoo Zurich |
Wright P.C.,Center ValBio
International Journal of Primatology | Year: 2015
All habitats of Madagascar go through a dry season from April to September each year, resulting in a period of fruit scarcity lasting up to 6 months and creating selection pressure for adaptation to fluctuations in resources. Some Cheirogaleid lemurs, including mouse lemurs (Microcebus), use daily torpor and long-term hibernation during this period, saving energy through inactivity. Capture–recapture studies in some mouse lemur populations have suggested a pattern of biased sex ratio throughout the winter as a result of females hibernating while most males remain active. We studied winter activity in a captive population of Microcebus lehilahytsara, Goodman’s mouse lemur, in a large enclosure at Zoo Zürich, Switzerland using capture–recapture methods to determine how this behavior varies with sex and age, and what this pattern suggests about the ultimate cause of torpor use in this clade. Our results suggest that Goodman’s mouse lemurs use torpor to avoid seasonal food shortage, even though they experience less extreme seasonal variability of food availability than western dry forest mouse lemurs. Male and female Goodman’s mouse lemurs are equally capable of winter torpor, and most remaining active individuals are young that have not sufficiently fattened. This suggests that the “ideal” winter behavior for both males and females is torpor, which ultimately avoids periods of seasonal food scarcity. © 2015, Springer Science+Business Media New York.
PubMed | University of Zürich, University of Wollongong, ETH Zurich, Leibniz Institute for Zoo and Wildlife Research and 3 more.
Type: | Journal: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology | Year: 2015
Methane (CH4) production varies between herbivore species, but reasons for this variation remain to be elucidated. Here, we report open-circuit chamber respiration measurements of CH4 production in four specimens each of two non-ruminant mammalian herbivores with a complex forestomach but largely differing in body size, the collared peccary (Pecari tajacu, mean body mass 17kg) and the pygmy hippopotamus (Hexaprotodon liberiensis, 229kg) fed lucerne-based diets. In addition, food intake, digestibility and mean retention times were measured in the same experiments. CH4 production averaged 8 and 72L/d, 18 and 19L/kg dry matter intake, and 4.0 and 4.2% of gross energy intake for the two species, respectively. When compared with previously reported data on CH4 production in other non-ruminant and ruminant foregut-fermenting as well as hindgut-fermenting species, it is evident that neither the question whether a species is a foregut fermenter or not, or whether it ruminates or not, is of the relevance previously suggested to explain variation in CH4 production between species. Rather, differences in CH4 production between species on similar diets appear related to species-specific differences in food intake and digesta retention kinetics.
PubMed | Zoo Dortmund, University of Zürich, University of Wollongong, ETH Zurich and 2 more.
Type: Journal Article | Journal: Journal of animal physiology and animal nutrition | Year: 2016
Sloths are renowned for their low metabolic rate, low food intake and low defecation frequency. We investigated factors of digestive physiology and energy metabolism in four captive individuals (mean body mass 10.0SD 3.7kg) of a hitherto mostly unstudied sloth species, Linns two-toed sloth (Choloepus didactylus), in a 2-week digestion recording and 23-h respiration experiment on animals fed a standard zoo diet of vegetables and starchy components. Dry matter intake, defecation frequency and particle mean retention time (MRT) in the gastrointestinal tract (GIT) were 123g/(kg(0.75) day), once every 5days and >140h in three individuals, but 53g/(kg(0.75) day), daily and 82h in one individual that was apparently compensating for a period of weight loss prior to the experiment. In all animals, solute marker was eliminated at a faster rate than the particle marker, indicating digesta washing in the sloths GIT. The overall metabolic rate calculated from oxygen consumption matched the metabolisable energy intake in three individuals [17322 vs. 16844 kJ/(kg(0.75) day)] but not in the fourth one [225 vs. 698 kJ/(kg(0.75) day)], supporting the interpretation that this animal was replenishing body stores. In spite of the low food intake and the low-fibre diet (20926g neutral detergent fibre/kg dry matter), methane production was rather high accounting for 9.40.8% of gross energy intake (2.7% in the fourth individual), which exceeded literature data for ruminants on forage-only diets. These results corroborate literature reports on low intake, low defecation frequency, low metabolic rate and long MRT in other sloth species. The long MRT is probably responsible for the comparatively high methane production, providing more opportunity for methanogenic archaea than in other non-ruminant mammals to produce significant amounts of methane.
Hummel J.,Institute For Tierwissenschaften |
Findeisen E.,Institute For Tierwissenschaften |
Sudekum E.-H.,Institute For Tierwissenschaften |
Ruf I.,University of Bonn |
And 4 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2011
The circumstances of the evolution of hypsodonty (= high-crowned teeth) are a bone of contention. Hypsodonty is usually linked to diet abrasiveness, either from siliceous phytoliths (monocotyledons) or from grit (dusty environments). However, any empirical quantitative approach testing the relation of ingested silica and hypsodonty is lacking. In this study, faecal silica content was quantified as acid detergent insoluble ash and used as proxy for silica ingested by large African herbivores of different digestive types, feeding strategies and hypsodonty levels. Separate sample sets were used for the dry (n = 15 species) and wet (n = 13 species) season. Average faecal silica contents were 17-46 g kg-1 dry matter (DM) for browsing and 52-163 g kg-1 DM for grazing herbivores. No difference was detected between the wet (97.5±14.4 g kg-1 DM) and dry season (93.5±13.7 g kg-1 DM) faecal silica. In a phylogenetically controlled analysis, a strong positive correlation (dry season r = 0.80, p < 0.0005; wet season r = 0.74 p < 0.005) was found between hypsodonty index and faecal silica levels. While surprisingly our results do not indicate major seasonal changes in silica ingested, the correlation of faecal silica and hypsodonty supports a scenario of a dominant role of abrasive silica in the evolution of high-crowned teeth. © 2011 The Royal Society.
Hagen K.B.,University of Zürich |
Besselmann D.,University of Zürich |
Cyrus-Eulenberger U.,University of Zürich |
Vendl C.,University of Zürich |
And 6 more authors.
Zoo Biology | Year: 2015
Plains viscachas (Lagostomus maximus) are large South American, fossorial rodents susceptible to diabetic cataracts. Various aspects of their digestive physiology were studied in three different experiments with nine male and seven female adult animals and six different diets (total n of feeding trials=35). Viscachas achieved mean retention times of 23-31hr, which is of a magnitude also recorded in horses; these did not differ for solute or small particle (<2mm) markers. Secondary marker excretion peaks indicated coprophagy, and were rarer on high-protein as compared to grass hay-only diets. Mean resting metabolic rate was, at 229kJ/kg0.75/day, lower than expected for a mammal of this size. Digestible energy requirement for maintenance was 445kJ/kg0.75/day. At 1.6-2.7L/day, viscachas produced more methane than expected for a hindgut fermenter of their size. On diets that included concentrate feeds, viscachas excreted glucose in their urine, corroborating reports on the susceptibility of this species for diabetes when kept on energy-dense food. Viscachas had a similar apparent digestibility of protein, lipids, and macrominerals as other rodents, rabbits, or domestic horses. This suggests that whether or not a species practices coprophagy does not have a major influence on these measures. Viscachas resemble other hindgut fermenters in their high apparent calcium digestibility. With respect to a digestibility-reducing effect of dietary fiber, viscachas differed from rabbits and guinea pigs but were similar to horses, suggesting that small body size needs not necessarily be linked to lower digestive efficiency on high-fiber diets. © 2015 Wiley Periodicals, Inc.
Zimmermann N.,University of Zürich |
Pirovino M.,University of Zürich |
Zingg R.,Zoo Zurich |
Clauss M.,University of Zürich |
And 4 more authors.
Journal of Medical Primatology | Year: 2011
Background Upper respiratory tract disease (URTD) is a significant cause of morbidity in captive orangutans (Pongo abelii, Pongo pygmaeus), and the pathogenesis is often unknown. Methods The prevalence of respiratory disease in captive European orangutans (201 animals; 20 zoos) and possible predisposing factors were investigated. Results Bornean orangutans (P. pygmaeus) showed chronic respiratory signs significantly more often (13.8%) than Sumatran (P. abelii; 3.6%), and males (15.8%) were more often afflicted than females (3.9%). Hand-reared animals (21%) developed air sacculitis more often than parent-reared animals (5%). Diseased animals were more often genetically related to animals with respiratory diseases (93%) than to healthy animals (54%). None of the environmental conditions investigated had a significant effect on disease prevalence. Conclusion Results suggest a higher importance of individual factors for the development of URTD than environmental conditions. Bornean, male and hand-reared orangutans and animals related to diseased animals need increased medical surveillance for early detection of respiratory disease. © 2011 University of Zurich.
Steuer P.,University of Bonn |
Sudekum K.-H.,University of Bonn |
Tutken T.,University of Bonn |
Tutken T.,University of Mainz |
And 6 more authors.
Functional Ecology | Year: 2014
A key concept of body mass (BM) in niche separation of large herbivores assumes that the decrease in diet quality inherent to increasing BM (due to less selective feeding behaviour) is balanced by a simultaneous increase in digestive ability (due to longer retention times), resulting in no or less-than-expected reduction in digestibility (as measured in the animal as a result of diet quality and digestive ability). However, the second part of this concept has been challenged recently due to theoretical problems and mismatch with empirical data. A proxy for digestibility, such as metabolic faecal nitrogen (MFN), will comprise both information on diet quality and digestive ability in free-ranging animals. In captive animals, if diet is kept constant, such a proxy can exclusively indicate digestive ability. Comparing free-ranging and captive animals under such conditions, one would expect an increase in MFN with BM in captive animals and no relationship between these measures in free-ranging animals if BM was related to digestive ability. We compared captive ungulates on a consistent grass hay diet (17 species; 30-4000 kg BM) to a sample of free-ranging East African ungulates (19 species; 12-4000 kg BM). MFN was used as the major proxy for digestibility. In captive animals, there was no influence of BM on MFN (P = 0·466); for free-ranging animals, a significant decreasing effect of body mass on MFN (P = 0·002) and therefore diet quality was found at a scaling of BM-0·15. In conclusion, scenarios that assume a compensation of the evident decrease in diet quality with BM via an increased digestive ability are not supported by this study. This does not rule out other feeding-related factors in facilitating large BM, such as compensation by an increased diet intake. © 2014 British Ecological Society.
Rubel A.,Zoo Zurich |
Zingg R.,Zoo Zurich
Zoologische Garten | Year: 2015
More space for the elephants, more proximity for visitors. The new Kaeng Krachan Elephant Park marks a further milestone at Zoo Zurich. Thanks to the new management form of "protected contact" the elephants move around more freely, display their natural behaviour, maintain social contacts and even go swimming, and the public will have the chance to get closer to the animals than ever before.The Kaeng Krachan Elephant Park at Zoo Zurich is named after the largest national park in Thailand. The eclosure is dedicated to support projects to help protect Asiatic elephants in Thailand, which includes attempting to resolve the conflicts that oppose farmers and elephants.Zoo Zurich's commitment to the Kaeng Krachan National Park is reflected in its design and a series of educational exhibits. The park includes an observation hut and protective fencing and illustrates how Thai farmers can protect their plantations around the National Park. A hut in ruins and tracks leading along the footpaths display the destructive consequences a visit from the elephants may have. © 2014.