Data from: Translocations spur population growth but fail to prevent genetic erosion in imperiled Florida Scrub-Jays

Land and natural resource use that supports human society can restrict
populations to degraded and fragmented habitat, which catalyzes extinction
and biodiversity loss through the interplay of small population size and
genetic decay. Translocating individuals is a powerful approach for
overcoming direct threats from human development and reconnecting isolated
populations, although this strategy is not without risks. Consequently,
there is a pressing need to understand the demographic and genetic
outcomes of translocations in order to determine their conservation
efficacy. We achieved this by leveraging the rare opportunity of having a
nearly complete population pedigree from two decades of intensive
demographic monitoring coupled with temporal genomic sequencing and
simulations to evaluate how translocating Federally Threatened Florida
Scrub-Jays from five subpopulations into an area of restored habitat with
a small recipient population influenced their recovery. Translocations led
to an expanding core population that rapidly grew 10-fold in size,
primarily fueled by a small subset of highly successful translocated
individuals, with one breeding pair responsible for ~24% of the
population’s expected genetic ancestry for 15 years on average. This high
reproductive skew led to increased inbreeding and genetic erosion, despite
the population expansion and simulation results showing that the variance
of ancestral genetic contributions was likely reduced by translocations.
These mixed conservation outcomes stress the importance of genomic and
demographic monitoring, as well as the potential need for genetic rescue
to offset the consequences of reproductive skew in isolated populations
following translocations, regardless of demographic recovery, in order to
achieve long-term species viability.