Combine conservation biology and genetics and what do you get? An approach that involves the use of genetic information to deal with issues regarding the management and conservation of wild species, especially the conservation of endangered species, both plant and animal.
Wildlife conservation genetics is the merging of two disciplines thought once to be on different ends of the scientific spectrum. One is genetics, or the study of genes and inheritance, and it takes place in a lab. The other is conservation biology, or the study of populations and species that may be victims of habitat loss and/or environmental change, and it takes place in the field. The two disciplines have proven to be far from incompatible, however, serving instead to complement each other and provide guidance for researchers wishing to protect the natural world.
The application of genetics in the field of wildlife conservation is focused on a few key areas:
Managing Genetic Diversity
As discussed in my article about molecular ecology, one of the main issues in wildlife conservation and management is the loss of genetic diversity in a population. While there are debates regarding exactly what loss in diversity means, it has been shown that populations with lower genetic diversity often show reduced fitness, brought about by something called “inbreeding depression." Inbreeding depression results in a population with low genetic diversity where there are quite a number of harmful alleles.
One of the ways in which genetic diversity can be restored, and thus inbreeding depression combated, is to increase “gene flow", or the introduction of new alleles into a population. This can be done in the wild, by restoring native habitats and reducing isolation among populations, or it can be done in an “artificial" manner, through captive breeding and reintroduction programs. Extensive knowledge of the genetic profiles of organisms can help set up matings that will enhance genetic diversity.
Unfortunately, there are limited funds available to dedicate to endangered species conservation, and to conservation in general, and so scientists often find themselves having to carefully choose where to direct their efforts. Genetics can help greatly in this type of choice. Indeed, scientists use molecular techniques in order to identify conservation “units", which are essentially genetically distinct groups within a population. This information can then be a guide for researchers deciding which population is truly unique and worthy of conservation. There have been many cases in which scientists spent their energy on conserving two populations that were thought to be different species because of their morphological differences; the genetic data, however, showed them to be simply variations of the same species.
In our increasingly fragmented world, genetics can also aid in understanding a population’s relationship to its landscape and how changes in the landscape have and/or will affect that population. For example, for many species, highways present a considerable barrier to natural gene flow; essentially cutting off a population on one side of the road from a population on the other side. This could spell disaster and even extinction for one of the populations.
Genetics has also come to the rescue of large carnivores that are often viewed in a negative and suspicious light by the humans with whom they must share their homes. After the reintroduction of the wolf, for example, farmers would complain that predation on their livestock was caused by this ferocious predator. DNA analysis of the saliva from wounds on sheep actually demonstrated that the culprits were coyotes.
The word “forensics" always brings to mind shows like CSI and NCIS. Wildlife forensics is really not that much different. Illegal trafficking of endangered species of animals is quite a big market - some say third to drugs and arms. Molecular identification of species and individuals, mainly through genetics, provides investigators with tools for determining if a particular specimen belongs to an endangered species or population. As with all forensic evidence, these genetic identifications are used in courts to bring down criminals, which, in the wildlife business, can include poachers, whaling companies, falconers, and pet storeowners.
An Introduction to Molecular Ecology (Beebee and Rowe, 2006)
Principles of Conservation Biology (Groom et al., 2006)
C.L. Williams et al. "A Coyote in Sheep's Clothing: Predator Identification from Saliva." Wildlife Society Bulletin. 2003.
University of Washington (2007, February 27). African Carnage: One Year's Seized Ivory Likely Came From 23,000 Elephants. ScienceDaily.
A. Dizon et al. "Molecular Genetic Identification of Whales, Dophins and Porpoises." NOAA Technical Memorandum. 2000.