Sonntag, 15 November 2020 14:07

PLETZER, A. (2015)

Grundlagen für ein Erhaltungszucht-Programm für die nördliche Batagur-Schildkröte Batagur baska (Gray, 1830) (Reptilia: Testudines: Geoemydidae).

148 Bl. : Zsfassungen (2 Bl.) ; Ill., graph. Darst.
Graz, Univ., Masterarb., 2015

Zusammenfassung:

Zur Erhaltung der hochgradig gefährdeten nördlichen Batagur-Schildkröte (Batagur baska) ist ein umfassender Managementplan notwendig, damit ein gesundes weiteres Überleben der Tiere und eine spätere Auswilderung möglich ist. In der vorliegenden Arbeit wird zuerst ein Überblick über den aktuellen Bestand, sowie zu Biologie, Gefährdung, Schutz und Zuchterfolge gegeben. Zur Dokumentation aller vorhandenen Daten der Individuen in menschlicher Obhut, ein „Studbook“ (Zuchtbuch) konzipiert, womit es in Zukunft auch leichter möglich sein wird, Analysen der Populationsentwicklung zu erstellen und Änderungen des Bestandes und der Struktur nachzuverfolgen. Darauf aufbauend wurde mithilfe des Programms VORTEX eine PVA (Population Viability Analysis) für diese Art durchgeführt, bei der verschiedene Modelle zur Überlebensfähigkeit der Populationen berechnet wurden. Aufgrund der unzureichenden Datenlage sind die Ergebnisse dieser Modelle aber nur bedingt aussagekräftig. Für den Entwurf zukünftiger Vorgehensweisen wurden Fragestellungen formuliert, deren Beantwortung für einen strukturierten Managementplan erforderlich ist. Vor allem die Klärung der Verwandtschaftsverhältnisse von Zuchttieren untereinander sowie genetischer regionaler Unterschiede ist für eine Erstellung von geeigneten Zuchtplänen dringend notwendig. Des Weiteren wurden anhand umfassender Literaturrecherchen und mit aktuellen Erkenntnissen aus genetischen Analysen konkrete Handlungsempfehlungen abgeleitet. Generell kann gesagt werden, dass Batagur baska innerhalb eines Erhaltungszuchtprogramms wahrscheinlich eine genügend hohe Gendiversität erhalten kann, um nicht durch Inzuchtdepression vom Aussterben bedroht zu sein. Die Frage, ob noch genügend genetische Variabilität für eine erfolgreiche Wiederansiedelung vorhanden ist, kann hingegen aufgrund der vorliegenden Daten nicht beantwortet werden.

Summary:

For preservation of the rare and threatened turtle species Batagur baska a comprehensive management plan is necessary, so that a healthy survival and subsequent reintroduction is possible. For this purpose, an overview of the current population size, as well as a summary of the biology, hazards, protection and breeding success of the species is given. For documentation of all individuals in captivity, an International Studbook is created to facilitate subsequent analyses of populations and record and track changes of the structure of the population therein. Based on this data, the program VORTEX was used to conduct a PVA (population viability analysis), where various models with different input parameters were calculated. Due to insufficient data, the results of these models are only of limited significance. For the development of future conservation strategies, the most important open questions were identified. The clarification of relationships between the breeding animals and a better knowledge concerning regional differences of the genetic variability is essential for the establishment of suitable breeding plans. Furthermore, additional recommendations for species protection were derived from literature data and by evaluating results of the genomic analyses. Batagur baska is likely to maintain sufficient genetic diversity within a conservation breeding program in order to avoid the threat of extinction because of inbreeding depression. However, it remains unclear whether the genetic variability is sufficient for a successful reintroduction of the species in the wild.

pletzer-biblio

Freigegeben in P
Samstag, 07 März 2020 11:27

REHÁK, I. (2020)

The great turtle rescue.

ZOOQUARIA 107:  22-23.

Aus dem Inhalt: 

On 11 December 2001, during a joint operation of the Customs Ship Search and Cargo Command and the Agriculture Fisheries and Conservation Department,  about 10,000 live South East Asiatic turtles were seized in Hong Kong. The shipment, originally destined for the Chinese food market, had an estimated market value of $3.2 million. The conservation and scientific value of the confiscated animals, as well as the ethical aspects of the situation, were enormous, and incalculable in monetary terms. Turtles were placed at Kadoorie Farm and Botanic Garden in Hong Kong. It was an incredible job to take care of such a quantity of mostly damaged, wounded and ill turtles. The wider international cooperation proved to be essential in reducing at least in part the suffering of the turtles. EAZA’s swift reaction and the international rescue that followed were exemplary. The superb cooperation between the Kadoorie Farm and Botanic Garden, TSA and EAZA – namely the EAZA Executive Office, ARTAG, Rotterdam Zoo and 26 other zoos in 11 countries – resulted in the successful import of 988 turtles (285 Cuora amboinensis, 126 Orlitia borneensis, 283 Heosemys spinosa, 90 Heosemys grandis, 204 Siebenrockiells crassicollis) and their consequent housing in individual zoos. During the rescue operation, which attracted a huge amount of publicity and media coverage, EAZA demonstrated its ability to carry out a complicated international operation with speed and efficiency, and we can be rightly proud of that.

rehak-biblio

Freigegeben in R
Samstag, 10 Juni 2017 13:59

GERLACH, J. (2008).

Pelusios subniger parietalis Bour 1983 – Seychelles black mud turtle.

In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., and Iverson, J.B. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs No. 5, pp. 016.1-016.4, doi:10.3854/crm.5.016.parietalis.v1.2008, http://www.iucn-tftsg.org/cbftt/. http://www.iucn-tftsg.org/cbftt/.

Zusammenfassung:

The Seychelles subspecies of black mud turtle, Pelusios subniger parietalis (Family Pelomedusidae), is restricted to six islands of the Seychelles group. Five breeding populations exist and the wild population was estimated to be about 660 adults in 2005. Populations continue to decline due to ongoing marsh drainage. Legal protection of wetland habitats is urgently required and ongoing reintroduction to protected areas need to continue to secure the future of this species.

Freigegeben in G
Mittwoch, 07 Juni 2017 16:14

RHODIN; A.G.J. & GENORUPA, V.R. (2000).

Conservation Status of Freshwater Turtles in Papua New Guinea.

Asian Turtle Trade: Proceedings of a Workshop on Conservation and Trade of Freshwater Turtles and Tortoises in Asia
P.P. van Dijk, B.L. Stuart, and A.G.J. Rhodin, Eds.
Chelonian Research Monographs 2:129–136

General Comments:

Trade in turtles from PNG is strictly regulated by law as proscribed by the Fauna (Protection and Control) Act (Parker, 1981) (this Act is currently in the process of being amended). Papua New Guinea is also a CITES signatory since 1975. All exports of all turtles require permits to be issued by the Conservator of Fauna (currently the Dept. of Environment and Conservation). No turtles are listed by PNG as Protected Species, which would limit legal permitted export to at most 4 animals to legitimate approved zoological institutions. However, all marine turtles and two freshwater turtles, C. insculpta and P. bibroni are listed as Restricted Species, with narrow guidelines limiting any legal export to only a few animals for legitimate scientific purposes. The rest of the non-protected and non-restricted turtle species may be exported only with issued export permits, and then only for approved legitimate scientific and zoological purposes. Export of curios incorporating wildlife parts (e.g., turtle shell masks) also requires export permits.

At least on paper, PNG protects its wildlife and turtle resources fervently from export, with proper concern for their continued utilization at the local level by the native population. Unfortunately, control and enforcement of these regulations is badly lacking, and very few export permits for turtles are actually issued. A search of permits issued during the last 3 years yielded evidence of only a single specimen of E. subglobosa exported to Hawaii in 1996. Permits were also previously obtained in 1987 for export of one C. novaeguineae (actually C. pritchardi), and in 1977 for a few specimens each of C. siebenrocki, C. novaeguineae, E. subglobosa, and E. novaeguineae, with only one specimen each of C. insculpta and P. bibroni (AGJR, pers. obs.).

Trade in New Guinea turtles at present appears to be restricted primarily to the international exotic pet industry. There appear to be significant levels of illegal export trade along the southern PNG – Irian border, as described above for the different species traded along this route. Some of this trade may pass through Daru, an off-shore regional port and air facility with a long history of illegal wildlife trade and also a major regional market for the sale of marine turtle meat. No similar trade appears to occur along the northern PNG – Irian border. The reasons for the difference reflect the higher levels of border control present along the northern border. Illegal export via air or ship from major ports such as Port Moresby probably also occurs, especially for vulnerable species like C. pritchardi which occurs close to Port Moresby. The Dept. of Environment and Conservation has inadequate manpower and resources to inspect and control these probable avenues of illegal trade.

As mentioned above for E. novaeguineae, the international food trade does not yet appear to have significantly impacted populations of turtles in New Guinea. However, as populations of heavily traded species in southeast Asia are depleted, the export routes for the pet trade currently emanating from New Guinea will probably convert and begin to trade increasing amounts of turtles primarily for the food trade. If the freshwater turtle fauna of Papua New Guinea is to continue to survive as a viable and sustainable resource base for utilization by the native population, and if we are to avoid the consumption of this resource in international exotic pet and food markets, then stricter adherence to existing laws and necessary control and inspection at probable export sites needs urgently to be implemented.

Freigegeben in R

Chelodina oblonga Gray 1841 – Northern Snake-Necked Turtle.

In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs No. 5, pp. 077.1–13, doi:10.3854/crm.5.077.oblonga.v1.2014, http://www.iucn-tftsg.org/cbftt/.

Summary:

The Northern Snake-necked Turtle, Chelodina (Macrochelodina) oblonga (Family Chelidae), until very recently known as C. (M.) rugosa, is a fairly large freshwater turtle (carapace length to 360 mm) with a broad distribution in tropical northern Australia and southern New Guinea. Its preferred habitats are seasonal wetlands on the coastal floodplains and adjacent hinterlands. These habitats undergo extensive flooding during the tropical wet season, with declining water levels during the following dry season; many waterholes dry completely. The species survives the dry season by migrating to permanent water or by estivating under the mud of dried waterholes. It is a highly prized food item among Aboriginal people, and turtles are collected each year in a harvest that has occurred for many millennia. The species is exclusively carnivorous and feeds on a range of fast-moving aquatic invertebrates, tadpoles, and fish. It is a highly fecund, fast-growing, and early-maturing species in comparison to most other Australian chelids. Its habit of nesting underwater makes it unique among all turtles. Nesting commences in the wet season (February) and is mostly complete by July (mid-dry season), though gravid females can be found as late as September if waterholes remain inundated. Eggs are laid in holes dug in mud under shallow water in the littoral zone of flooded waterholes. Embryonic development remains arrested while the nest remains flooded, but recommences when floodwaters recede and the ground dries. Embryonic development proceeds during the dry season and hatchling emergence coincides with the heavy rainfall or flooding in the following wet season. The species remains common in all the major river systems across northern Australia and southern New Guinea, and is sustainably harvested for traditional consumption in Australia, but is under some threat there from pig predation.

Freigegeben in K

Chelodina  longicollis (Shaw  1784) – eastern  long-necked  turtle, common long-necked turtle, common snake-necked turtle.

In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs 5: 031.1-031.8, doi:10.3854/crm.5.031.
longicollis.v1.2009, http://www.iucn-tftsg.org/cbftt/.

Summary:

The eastern long-necked turtle, Chelodina longicollis (Family Chelidae), has a wide distribution throughout southeastern Australia. It occupies a broad range of freshwater aquatic habitats but is more abundant in shallow, ephemeral wetlands often remote from permanent rivers. Its propensity for long distance overland migration, coupled with a low rate of desiccation and the capacity to estivate on land, enable it to exploit highly-productive ephemeral habitats in the absence of competition from fish and other turtle species. In wetter periods, such habitats provide optimal conditions for growth and reproduction. In drier periods, however, turtles may need to seek refuge in permanent water where high population densities and low productivity can lead to reduced growth rates and reproductive output. The species is an opportunistic carnivore that feeds on a broad range of plankton, nekton and benthic macro-invertebrates, carrion, as well as terrestrial organisms that fall upon the water. It is relatively slow to mature (7–8 yrs for males and 10–12 yrs for females), lays between 6 and 23 hard-shelled eggs during spring and late summer, and can produce up to 3 clutches per year. Although currently considered common and not under major threat, the most widespread conservation concern for C. longicollis is high nest predation from the introduced fox (Vulpes vulpes), and roads, pest fencing, and habitat changes brought about by prolonged drought and climate change, which present localized and potential future threats for certain populations.

Freigegeben in K
Mittwoch, 07 Juni 2017 11:44

GRAY, J.E. (1856)

On some new species freshwater tortoises from North America, Ceylon and Australia.

Ann. Mag. Nat. Hist. (2) 18: 263-268.

Inhalt:

In dem Artikel werden v erschiedene Gattungen revidiert, so etwa Pseudemys von emys getrennt und verschiedene neue Arten beschrieben, darunter Chelodina colliei und Chelodina sulcata

Freigegeben in G
Mittwoch, 07 Juni 2017 07:20

WEBB, R. G. (1962)

North American Recent Soft-shelled Turtles (Family  Trionychidae)

University of Kansas Publications, Museum of Natural History 13 (10): 429-611.

Summary (Auszug):

In North America, soft-shelled turtles (genus Trionyx) occur in northern México, the eastern two-thirds of the United States, and extreme southeastern Canada. The genus fits the well-known Sino-American distributional pattern. In North America there are four species. Three (ferox, spinifer and muticus) are well-differentiated [591] and one (ater) is not well-differentiated from spinifer. Characters of taxonomic worth are provided by the following: size; proportions of snout, head and shell; pattern on carapace, snout, side of head, and limbs; tuberculation; sizes of parts of skull; number of parts of carapaces; and, shape and number of some parts of plastra. Many features show geographical gradients or clines. T. ferox is the largest species and muticus is the smallest. Females of all species are larger than males. With increasing size of individual, the juvenal pattern is replaced by a mottled and blotched pattern in females of all species; adult males of spinifer retain a conspicuous juvenal pattern, whereas the juvenal pattern is sometimes obscured or lost on those of ferox and muticus. The elongation of the preanal region in all males, and the acquisition of a "sandpapery" carapace in males of spinifer occur at sexual maturity. There is a marked secondary sexual difference in coloration in a population of T. s. emoryi (side of head bright orange in males and yellow in females). The sex of many hatchlings of T. s. asper can be distinguished by the pattern on the carapace. Slight ontogenetic variation occurs in some proportional measurements. Large skulls of ferox and some asper (those in Atlantic Coast drainages) have expanded crushing surfaces on the jaws. Considering osteological characters, muticus is most distinct; there is less difference between ferox and spinifer than between those species and muticus.

Freigegeben in W
Freitag, 02 Juni 2017 15:43

KUCHLING, G. (2010)

Taxonomy and nomenclature of the longneck turtle (genus Chelodina) from south-western Australia.

Records of the Western Australian Museum 25: 449–454
DOI 10.18195/issn.0312-3162.25(4).2010.449-454

Abstract:

Gray (1856) recognised Chelodina colliei from south-western Australia as a different species from Chelodina oblonga Gray, 1841 from ‘Western Australia’. In addition, Gray (1873) specifically mentioned specimens of C. oblonga from the Port Essington region of today’s Northern Territory. Boulenger (1889) synonymized C. colliei with C. oblonga, a view followed by later reviewers for over seven decades. Goode (1967) and Burbidge (1967) both reinstated Gray’s original concept that the longneck turtle of south-western Australia represents a distinct species, but erroneously applied and restricted the name C. oblonga to the south-western Australian species. Thomson (2000) detected this nomenclatural error and subsequently applied to the International Commission on Zoological Nomenclature (ICZN case 3351, Thomson 2006) to give precedence to rugosa over oblonga whenever the two were considered to be conspecific and to place on the official lists the names colliei, oblonga and rugosa, thus leaving colliei as the only available name for the south-western Australian Chelodina. Since then, the name Chelodina colliei was again used by several authors for the south-western Australian taxon, including in books and checklists (Bonin et al. 2006; Fritz and Havaš 2007; Iverson 2007). With case 3351 still under consideration by the ICZN, McCord and Joseph-Ouni (2007) further aggravated the nomenclatural confusion regarding the south-western Australian longneck turtle by fixing a ‘neotype’ for C. oblonga and by describing the genus Macrodiremys for C. oblonga (= colliei), both actions in violation of Articles 75.6 and 82.1 of the 1999 ICZN Code.

Freigegeben in K

Geochelone platynota (Blyth 1863) – Burmesische Sternschildkröte, Kye Leik.

Chelonian Research Monographs 5, doi 10.3854/crm.5.057.platynota.vl.2011.

Die Burmesische Sternschildkröte, Geochelone platynota (Familie Testudinidae) ist eine mittelgroße Landschildkröte (Carapaxlänge etwa 30 cm), die die Trockenzone von Zentralmyanmar endemisch besiedelt. Wenig ist bezüglich ihrer Ökologie im natürlichen Habitat bekannt. Die Art lebt in so genannten xerophytischer (Trocken-) Vegetation, die typisch für die Trockenzone ist, besiedelt aber auch Grasland und gut genutzte Weiden und Hecken sowie landwirtschaftlich genutzte Felder. Ihre Nahrung besteht meist aus Gras und anderer Vegetation, aber Früchte, Pilze, Schnecken und Insekten werden auch gefressen und im Kot nachgewiesen. Die Paarungen erfolgen von Juni bis September gefolgt von Eiablagen von Oktober bis Februar. Die durchschnittliche Eizahl pro Gelege (n=27) lag bei 4,4 Eier, und es gab eine positive Korrelation zwischen der Größe der Weibchen und der Gelegegröße. Basierend auf den Daten, die an einer begrenzten Anzahl an Tieren erhoben werden konnten, ist die Home Range (genutzte Habitatfläche) für die Männchen größer als für Weibchen. Während der kühlen und trockenen Jahreszeit sinkt die Aktivität, und die Schildkröten ruhen im Bambusdickicht, unter Überhängen oder steinigen Höhlen. Geochelone platynota lebt makro- und mikrosympatrisch mit Indotestudo elongata in der Trockenzone, aber die ökologischen Beziehungen zwischen den beiden Arten sind kaum verstanden. Die wenigen Daten, die es gibt, lassen vermuten, dass G. platynota in der Wildnis mittlerweile als ökologisch ausgerottet angesehen werden muss. Dies ist das Ergebnis der aus der Historie bekannten lang anhaltenden Nutzung als Nahrung und dem in jüngster Zeit stark forcierten, illegalen Absammeln der Tiere für die internationalen Nahrungsmittel- und Haustiermärkte. Die letzten bekannten wild lebenden Populationen in den Schutzgebieten Shwe Settaw und Minzontaung sowie in Myaleik Taung sind nun so stark dezimiert, dass sie nicht mehr überlebensfähig sind. Zukünftige Erhaltungsmaßnahmen hängen davon ab, ob es gelingt, Methoden zur Nachzucht in menschlicher Obhut vor Ort in Myanmar zu entwickeln und entsprechende Wiederauswilderungsprogramme zu etablieren. Derzeit werden Nachzuchten in verschiedenen Einrichtungen in Myanmar erbrütet, allerdings verhindert die anhaltende Wilderei die Wiederansiedlung der Schildkröten in den Schutzgebieten.

 

platt-biblio

Freigegeben in P
Seite 1 von 5
© Peter Dollinger, Zoo Office Bern hyperworx