M. Zemanek’s research while affiliated with Geofizyki Kraków and other places

... Research carried out in the 1980s and 1990s showed that, in the northern part of the distribution area, embryos did not complete their development or overwintering hatchlings died because of severe frost (Zemanek, 1991;Andreas & Paul, 1998;Najbar & Szuszkiewicz, 2005). Nevertheless, evidence of successful reproduction was found for example in central Poland (where hatchlings were recorded in spring, Zemanek & Mitrus, 1997) as well as in Germany (Andreas et al., 1996). Based on summer temperatures in Poland, Zemanek (1991) estimated that E. orbicularis could have successfully reproduced in 23 out of 57 seasons between 1931 and 1988. ...

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Frequency of successful reproduction and time of nest emergence of hatchlings of the European pond turtle in the northern part of its distribution area

... Not all females produce two clutches, and not every female reproduces each year (Kotenko 2000). After approximately 3 mo of incubation in the nest chamber, hatchlings emerge from August to late October (Lebboroni and Chelazzi 1998;Rössler 2000;Novotný et al. 2004;Mitrus et al. 2012;Ayaz et al. 2017) although hatchlings may overwinter in nest chambers and emerge the following spring (Servan 1998;Kotenko 2000;Mitrus and Zemanek 2003;Najbar and Szuszkiewicz 2005;Ayaz and Çiçek 2011). Overwintering in the nest is quite widespread among turtles (Gibbons and Nelson 1978;Gibbons 2013) and the physiological ecology of overwintering on hatchling turtles are well documented (Costanzo et al. 2008). ...

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Nesting activity and reproductive success of Emys orbicularis in Babat Valley (Gödöllő, Hungary)

... The decline of the E. orbicularis population is predominantly of anthropogenic origin, due to direct 64 destruction of their nesting sites, habitat loss from changes in land use (Schneeweiß, Breu, 2013), 65 environmental pollution (Savic, 2010), collecting for trade ( as incubation of eggs and overwintering of hatchlings. Reducing mortality rates in these early 75 stages is crucial to increase the population size of E. orbicularis (Mitrus and Zemanek, 1998). 76 There are several strategies to achieve this. ...

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Can artificial rearing benefit the natural breeding of European pond turtle (Emys orbicularis) in its northern distribution range?

... Mitrus (2005) suggested that the tiny hatchlings of E. orbicularis hardly accept food in captivity, thereby limiting the effectiveness of this approach to headstarting. Mitrus and Zemanek (1999) also found very slow growth of E. orbicularis hatchlings in the first months after the hatch and an apparent incapacity to feed. In our study, food was readily accepted by all individuals of both groups by one week after hatching. ...

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Head starting european pond turtle (Emys orbicularis) for reintroduction: Patterns of growth rates

... For males, estimates range from 8-9 years to 12-13 years, while for females the corresponding values are 11-12 years or 18-20 years (Girondot andPieau 1993, Baron andDuguy 2000). Mitrus (2004) indicates that males mature at 11 years of age and females after 15 years in Poland. Bozhansky and Orlova (1998), for Russian populations, and Kotenko (2000) for Ukrainian populations, suggest that males and females mature at the same age, 5-8 years. ...

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Successful reintroduction of the European pond turtle Emys orbicularis with a small number of founders: results from a 20-years small-scale experiment

... Its populations declined considerably due to the reduction in suitable wetlands in recent decades 64 . The life history of the European pond turtle is characterized by a long lifespan, delayed sexual maturity and low reproductive output 26,43,65 . It can lay its eggs in different habitats, such as forest ponds, fish ponds, recreational lakes, bogs, marshes, backwaters, canals, and slow small watercourses 26,[64][65][66] , making it an optimal model species for studying predation effects and designing nest protection solutions based on this. ...

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Testing how environmental variables affect the survival of freshwater turtle nests and hatchlings using artificial nests and dummy hatchlings