Elephants Elephants - Wildpro - Twycross Zoo

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14
12
10
8
6
4
2
0
Fig. 10. Elephant births in European collections
1981
1984
3.7.3 Asian Elephant
NORTH AMERICA
The situation is not good, and the population is not self sustaining. Fecundity
is poor and first year mortality is almost 30%. The analysis was carried out on
the regional studbook current to January 1999. The oldest breeding cow was
32, again highlighting the problem that captive females in North America
become reproductively senescent in their mid 30s (Wiese 2000). Recently it
has been shown that the average Asian elephant life expectancy in North
America is 35.9 years (Wiese and Willis 2004). Using current fecundity and
mortality figures the female population of 241 will dwindle to 13 animals at
the end of a 50 year projection; however with a realistic increase in fecundity
and drop in mortality the population could recover. One major problem was
that there were only 18 bulls in 12 institutions. Thus a similar picture emerges
with a need for an increased conception rate in fertile females and a reduction
in infant mortality. However recently (Faust et al 2005) it has been shown that
the population is not self-sustaining and is declining at 2% per year due to
insufficient birth rates. A large increase in the number of births is required to
reverse this trend.
EUROPE
1987
1990
1993
Years
1996
1999
2002
2005
Ton Dorresteyn (the EEP coordinator), and Rob Belterman (the studbook
keeper), both at Rotterdam Zoo provided all the information. The population
in the studbook in October 2005 was 319 (63.256). There are 41 living
founders. Although young being born per year is increasing, the mortality
rate in the first year (taking data from 1980-2005) for animals born in Europe is
35% with most of these being on the day of birth (30%); a similar problem to
African
Af. Surv. Y1
Asian
As. Surv. Y1
77