Żółwie lądowe > Żółwie lamparcie
Teoś (aka Pączek)
Logfil:
Zapomniałem dodać, że w badaniach Rall i Fairalla wskazano również na spożycie znanego nam wszystkim mlecza, ściślej: Sonchus oleraceus – więc jest to również roślina, która spełnia warunek „roślina zjadana w naturalnym środowisku”.
Inne ciekawe informacje dotyczące żółwi lamparcich (w oparciu o prace z czasopism naukowych), oczywiście w większości wypadków wymagające dodatkowych badań weryfikujących (w razie potrzeby służę pdfami):
1) W innej swojej pracy (Occurrence and Activity Budget of the Leopard Tortoise Geochelone Pardalis, in Northern Tanzania, "Tanzania Journal of Science" 1(27), 2001, s. 87-99) Kabigumila badał występowanie i aktywność (tylko poranną) żółwi lamparcich w latach 1993-1996. Ponownie trudno opisać tu wszystkie wyniki, lecz ogólnie rzecz biorąc:
a) występowanie: niska trawa (51,5%), Road and track verges (33,9%), Bush undergrowth (6,7%) i shambas (tj. tereny uprawne, ogrody) (3,6%);
b) aktywność (poranna): przemieszczanie się (46,3%), jedzenie (37,2%), odpoczynek (13,6%), zaloty (1,9%), picie (0,9%).
Powyższe dane różniły się w zależności od wieku żółwi, np. dorosłe częściej odpoczywały, a więc również częściej przebywały w Bush undergrowth. Ogólnie zapewne częściej w południe, przy największym nasłonecznieniu…
2) Wpływ suplementacji wapnem na rozwój został opisany w pracy: Fledelius, Jorgensen, Jensen, Brimer, Influence of the calcium content of the diet offered to leopard tortoises (Geochelone pardalis) (w: “Veterinary Record” 156, 2005, s. 831-835). Część opisu diety: “The tortoises were offered a basic diet, relatively poor in calcium, consisting of a mixture of chopped vegetables such as carrots, iceberg lettuce, cucumber, sweet peppers, tomatoes and hay. No ingredients known to be rich in protein, such as alfalfa, were included in the diet. Each day, each group was given 155 g of this fodder. The average calcium content of the daily feed ration for each group was estimated to be approximately 60 mg over the whole experimental period (Moeller 1996). In addition, each group received the same quantity of a supplement containing vitamins, magnesium and sodium (Vitamin and Mineral Mixture for Birds and Reptiles; Diafarm) (Table 1). The diets of groups 2, 3 and 4 were further supplemented with calcium to give the total calcium contents specified in Table 2;the tortoises in group 2 received the calcium supplement (Diafarm) for reptiles (based on calcium carbonate) at the recommended dose of 2•55 g/kg fresh weight of prepared feed, and the tortoises in groups 3 and 4 were provided with pure calcium carbonate to achieve the higher levels of calcium given to these two groups.” Wybrane wyniki/obserwacje: “No shell distortion, including pyramidal doming, was seen, and only a softening of the shells was observed. The weight of the tortoises in group 1 increased on average by 7•5 per cent, the lowest rate of growth observed in any of the four groups. Group 2 had the slowest growth rate at the beginning of the study, but the rate gradually increased and over the whole period their weight increased on average by 11•8 per cent. Group 3 consistently had the highest rate of growth, with a total average gain of weight of 14•5 per cent by the end of the study.The growth rate of group 4 increased steadily but its total average weight gain was only 8•1 per cent. The tortoises which received no calcium supplementation (group 1) became weak and lethargic, and their shells were generally soft; one had an extremely soft shell but survived. Unfortunately, three of the six tortoises in group 2 (receiving the calcium intake recommended by Diafarm) died during the study. They were lethargic, had soft shells and oedema, and a black extravasion could be observed on the plastron.The cause of death was ascertained to be a flagellate infection with Hexamita parva, which had infected the tortoises before the study. Although they had been treated with metronidazole (Flagyl; May and Baker) and seemed to have recovered, they did not thrive and died within four months of beginning the study. Of the remaining three tortoises in group 2, two had soft shells and one was thriving. The tortoises which received three and nine times the recommended level of calcium supplementation (groups 3 and 4) were all lively and thriving; they had hard and well developed shells.” Dalej: „The tortoises which were given three times the recommended calcium supplementation (group 3) were in a good state of health,and they had the highest growth rate. Scanning showed that there was a significant increase in their body calcium content. Postmortem, there were multifocal calcifications of the connective tissue in the lungs, focal areas of calcification in the heart, fatty degeneration of the liver, and the femurs had thick cortices, suggesting that calcium had been given in excess. The tortoises receiving nine times the recommended calcium supplementation (group 4) were also in a good state of health, but their growth rate was lower than that of groups 2 and 3, and scanning showed that there had been a significant increase in their body calcium.” WAŻNE: “The results of this study suggest that providing a mixture of chopped vegetables, powdered with the recommended calcium supplement of Diafarm, that is, 2•55 g calcium/kg fresh feed, may not meet the needs of captive leopard tortoises or other tortoises, if the basic diet is inherently deficient in calcium.”
3) Wzrost i kolor karapaksu opisał Kabigumila w jeszcze innej pracy (Growth and carapacial colour variation of the leopard tortoise, Geochelone pardalis babcocki, in northern Tanzania, „African Journal of Ecology” 3(38), 217-223) – wyniki dotyczące wzrostu nie są zaskakujące: najszybciej rosną młode (szczególnie między 21 a 33 miesiącem życia – to z innej, przywołanej w tym artykule pracy) oraz samice, które osiągają większe rozmiary. Kolor karapaksu był natomiast znacząco różny pomiędzy dwoma badanymi obszarami, tj. Serengeti i Arusha. Inna praca na temat wzrostu: Hailey A., Lambert R.K., Comparative growth patterns in Afrotropical giant tortoises (Reptilia Testudinidae), “Tropical Zoology” 15, 2001, s. 121-139 – a także w następnym punkcie.
4) Temperatura powietrza i ciała oraz zachowanie żółwi z nimi związane opisują McMaster i Downs (Thermoregulation in leopard tortoises in the Nama-Karoo: The importance of behaviour and core body temperatures, „Journal of Thermal Biology” 38, 2013, s. 178-185). Gdzie były prowadzone badania? „Field work was conducted on a 5500 ha area of a 26,000 ha mixed commercial sheep and game farm in the De Aar District, Nama-Karoo biome, South Africa (31104’S, 23141’E). Vegetation here is classified as grassy dwarf shrubland (Palmer and Hoffman, 1997). Average annual rainfall is low (200–400 mm) and the area has its highest rainfall in late summer and autumn (McMaster, 2001). Daily temperatures range from 5 to 39 1C in spring (Sept–Nov) and summer (Dec–Feb), and from ?5 to 26 1C in autumn (Mar–May) and winter (June–Aug) (McMaster, 2001).” Wyniki (mała cząstka): “Body mass of tortoises showed a range of body size between individuals but did not differ significantly when years and seasons were considered”. I dalej (Tb to oczywiście temperatura ciała, Ta otoczenia): „In summer, core T b s of all tortoises oscillated on a daily basis between 25 1C and 35 1C, with a minimum of 17.0 1C and a maximum of 38.0 1C, independent of T a minimum and maximum profiles (Fig. 1). In the morning, the tortoises were thermoconformers and their T b and T a minimum profiles rose similarly until T b reached around 35–36 1C (Fig. 1). At this temperature the tortoise T b became independent of T a maximum profile, which could rise to over 50 1C. As T a cooled in the afternoon and overnight, the T b of the tortoise lagged against T a minimum and maximum profile, such that the tortoise became a thermoregulator; although the T a minimum profile reached below 10 1C, the tortoise T b never reached below 22 1C (Fig. 1). In winter, core T b of all tortoises oscillated above T a minimum profiles on a daily basis between 8 1C and 30 1C on most days, with a minimum recorded T b of 3 1C and a maximum of 32 1C (Fig. 1).” W pracy tej znajdują się odniesienia do dwóch innych prac – według pierwszej, najlepsza temperatura ciała (tj. preferowana w naturze) wynosi 28,7C; według drugiej 29,1C w chłodniejszym klimacie, a 32,6C w cieplejszym.
5) Badania wykazały, że nie ma dwóch podgatunków, choć istnieją różnice – praca zbiorowa: Fritz U., Daniels S.R., Hofmeyr M.D i inni, Mitochondrial phylogeography and subspecies of the wide-ranging sub-Saharan leopard tortoise Stigmochelys pardalis (Testudines: Testudinidae) – a case study for the pitfalls of pseudogenes and GenBank sequences, „Journal of Zoological Systematics and Evolutionary Research” 4(48), 2010, s. 348-359. Szczegóły są bardzo techniczne, niech za podsumowanie wystarczy ostatnie zdanie, WAŻNE: “Hence, we conclude it is best to return to the situation before S. p. babcocki was revalidated [chodzi o pewien artykuł z 2006 roku, którego wartość podważają ci autorzy]: The usage of subspecies within S. pardalis should be abandoned.” Autorzy stawiają także ciekawą hipotezę: „the differences in the mitochondria diversity of leopard tortoises from the south and north of their ranges, with a distinctly higher number of clades and haplotypes in the south, might indicate that the species originated in southern Africa and that the northerly regions were colonized later.” Co ciekawe: “Mitochondrial differentiation in S. pardalis is not paralleled by obvious morphological variation, although it is well known that considerable size differences exist in different regions. Leopard tortoises from the far south and the far north are much larger than tortoises from the centre of the range”.
6) Szybkość wzrostu żółwi w niewoli i tych na wolności – nie dziwi fakt, że zdecydowanie szybciej rosną te trzymane w niewoli. Więcej szczegółów: zob. Ritz J., Hammer C., Clauss M., Body Size Development of Captive and Free-Ranging Leopard Tortoises (Geochelone pardalis), “Zoo Biology” 29, 2010, s. 517-525.
7) Preferencje zapachów były badany w pracy: Douglass K.R., Lockhart C.R., Edwards M.S., Assessment of Leopard Tortoise (Geochelone Pardalis) Scent Preference, NAG Proceedings 2009, i właściwie wszystko jest wyłożone w abstrakcie: “It is suggested tortoises are attracted to certain ingredient scents. The preference for scent of ginger, anise, rose, and a control (water) among leopard tortoises was evaluated. Sixteen leopard tortoises (Geochelone pardalis) participated in a series of trials exposing them to pair-wise combinations of the three scents and control. Response criteria evaluated include position (left, right, no decision) and scent selection. [...] These results suggest there is no preference for ginger, anise, rose scents over each other or a control (water) among leopard tortoises.”
8 ) Dwie inne ciekawe prace: a) Hailey A., Coulson I.M., Habitat association of tortoises Geochelone pardalis and Kinixys spekii in Sengwa Wildlife Research Area, Zimbabwe, “Herpetological Journal” 5, 1995, s. 305-309; b) Mason M.C., Kerley G.I.H., Weatherby C.A., Angulate and leopard tortoises in the Thicket Biome, Eastern Cape, South Africa: populations and biomass estimates, “African Journal of Ecology” 2(38), s. 147-153.
Kamil56:
Fajne teksty. Jeśli trafisz jakieś fajne teksty tylko w ojczystym języku to wstaw. Po anglikańskiemu ciężko się mi czyta (nie jestem orłem z tego języka :) ).
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