The San Diego Zoo is conducting a research about California Condor to improve their management. Their work includes detection of West Nile Virus (WNV) and investigations into the potential cause of vaccine failure. Using this knowledge, they will develop improved vaccination models for WNV and avian influenza and strategies that will be effective under free-ranging conditions, says a person in charge on the zoo website.
They are also documenting the effects of acute and chronic lead exposure, from which over 12 free-ranging California condors have died. We will correlate all available blood, lead, bone, and feather lead data with mortality data and field histories to assess the direct and indirect effects of acute and chronic lead exposure in California condors.
Accordingly they exploring the significance of elevated liver copper levels. Several California condors that have died in the field have had higher than expected hepatic copper levels, but the significance of this is unknown. We will compare hepatic copper levels in captive and free-ranging birds of prey, and correlate these findings with clinical, field, and management histories, and postmortem findings.
Ongoing genomic analysis of this predator is aimed at identifying candidate genes for the chondrodystrophy mutation and supporting breeding management. Sequencing and characterization of a candidate locus are underway that could enable us to identify carriers of the chondrodystrophy allele and provide tools for improved management of this disease and its impacts on the condor populations.
As an additional strategy, they are evaluating markers to construct a linkage map to identify regions on condor chromosomes associated with the disease condition. Sequencing the condor genome is an emerging possibility, utilizing the newly emerging DNA sequencing technologies.
Finally, environmental toxicology studies are addressing the potential problem of condors feeding on marine mammal carcasses that could contain high concentrations of persistent organic pollutants such as PCBs and pesticides. The San Diego Zoo is preparing condor tissues obtained from pathology for gene expression analysis and hormone receptor cloning. The goal is to evaluate the sensitivity of condors to contaminants found in these marine mammal carcasses and to compare that to other species of birds known to have high and low sensitivities to similar chemicals.
The genetic changes occurring in endangered species might increase their extinction probabilities. Low population sizes leads to reduced genetic diversity and increased inbreeding. A low of genetic diversity means a reduced ability to adapt to environmental changes. Inbreeding is often associated to reduced reproduction and survival. Genetic factors might thus play an important role in species extinction -and therefore in their conservation.
Molecular genetic markers are often used to assess the genetic status of endangered species and populations. This information is then used to elaborate conservation plans designed to maximize genetic diversity and minimize inbreeding.