Reproductive Success of Relocated Desert Tortoises
Interview with SBCI Scientist, Rob Fleischer
Scientists found that male desert tortoises that had
been relocated from a threatened habitat to a new nearby home are
reproducing at a much, much lower rate than resident males.
paternity testing of 92 hatchlings by SCBI geneticists revealed that not
a single hatchling was sired by a re-located male. Learn
more about the team’s findings from Rob Fleischer, head of SCBI’s
Center for Conservation Genomics and senior author on the study.
Fleisher: We used DNA markers to determine the reproductive success
of male and female desert tortoises that had been translocated for
mitigation, compared to the reproductive success of the local males and
females that already lived there.
Four years after the translocation, we found that female
tortoises that had been moved had reproductive success that was
equivalent to the local resident females. That was not true for the
males. We found that of the offspring for whom we could identify fathers
during that timeframe, all had been fathered by resident males and none
that we identified were fathered by translocated males.
No matter how you look at our data set, it is very clear
that the resident male tortoises are reproducing at a much higher rate
than the translocated males. The resident males, it seems, are mating,
while the translocated males are kind of reproductive duds…