Conservation Genetics

Gene Pools

A gene pool is a diverse range of varied genes within a population of species (Study.com, 2015). Different genes are what causes different traits within organisms; whether the trait be behavioural, physical, or physiological (Trut, 2009).

Genetic diversity is more successful when the gene pool is significantly larger and more diverse; this makes for a larger variety of traits within a species, which makes it easier for the species overall to cope against changing external factors (Pujari, 2015). One individual may be better at coping colder winters by having a more durable winter coat, and whilst others may die from the cold, its succession would keep it alive and give it stronger chances at successfully breeding and passing down its successful gene.

If a species were to be completely the same with no gene variety, a single factor that they are not adapted to could potentially wipe out the entire species in a single bout. This is called an unfavourable inherited trait, where a trait is common in a species that does not benefit them or support their survival chances (National Gardening Association, 1999).

For example, a disease could spread across a population, but if the gene pool was diverse, several individuals could have an immunity towards the disease. Whilst others in its species die, the ailment is ineffective to others, allowing them to survive and continue the population.

Organisms with larger gene pools are more likely to survive environmental changes than smaller gene pools due to the flexibility of genes and the ability to change. A small gene pool will struggle to successfully adapt to harsh changes, which puts them at risk to extinction of the population, and risks chances of inbreeding within the population (Scoville, 2015).

In order to keep the gene pool diverse, organisms can immigrate or emigrate into new populations, or can develop mutations, although the chances of mutations becoming effective is rare(Allen et al, 2015). An issue with migration is that the population can reduce drastically from individuals leaving; on the other hand it could also have the potential to expand if other populations migrated to join theirs.

Panthera Pardus Orientalis are currently struggling with keeping genetic diversity within their population. With under 70 individuals in the wild, Panthera Pardus Orientalis are finding it difficult to find enough gene diversity within breeding, thus inbreeding becomes a prominent issue in relation to the species. It has been shown that through the result of inbreeding in the wild, Panthera Pardus Orientalis are developing severe heart murmurs, which will hinder their survival more so (Amur Leopard Group, 2012). The situation is being influenced by human intervention, as conservations across the globe are breeding with each other’s captive leopards and releasing the new gene pool into the wild, where they’ll hopefully implement a difference in the diversity of the wild population.

Genetic Diversity

Genetic Diversity is what allows species to cope with changes within the environment. This is heavily influenced by the gene pools of the species, since the diversity of genes are what makes a gene pool.

Genetic diversity is one of three factors that make up Biodiversity, the others being ecosystem diversity and species diversity. The more influences that are made between the three factors, the stronger the biodiversity of that area (Preshoff, 2015).

Gene pools are not about the number within a population, rather the number of differences found within the population. There could be a lot of a species in a population, but a very tiny gene pool. This effect is known as bottlenecking; where there are lots within a population but little diversity to each.

Mirounga (elephant seals) are known to suffer from bottlenecking; during the 1800’s they were hunted to use their blubber for oil, leaving only 50-100 individuals within a colony. Despite this, by 2005 their population rose from its reduced number to over 100,000; most genetically related to the survivors of the original colony (Meir, 2013). Despite their large numbers, their genetic variability is heavily strained, and through climate change the seas are warming, which the population are struggling to cope against. The environmental factor of temperature of the ocean is affecting the gender of born pups; in which far too many males are being born, and not enough females. This can cause issues for the species in the future, as many seals will be unable to pair or mate up and violence towards competitive males can become extreme enough to make seals turn on each other (Williams, 2013).

If a gene pool is reduced enough, the lack of variety in genes increases the chances of genetic mutations through breeding, as well as a larger susceptibility to disease. The effects caused from negative mutations and mortality from diseases reduces the population further, which in turn reduces the chances of reproductive rates of the species, further hindering it and its potential future.

A fluctuation in genetic diversity will provide more characteristics for a species, which will increase immunity, and decrease the probability of negative mutations. This maintains a healthy gene pool, which improves the overall survival opportunities of the population.

For example, Liana Vines are a type of plant that grows up from the ground and travels up trees until they reach the tree’s canopies (see figure 8). These have a symbiotic relationship with the trees, as the trees allow them the ability to grow further, and in turn the vines grow thick stems to support the trees and keep them splinted against potential weather that could knock them over. The relation of the vines to the trees improves the tree’s ability to survive, and thus their leaves/seeds/fruits are spread for other animals to digest and transport across the forest. Each individual species fit together in a niche to work together and keep the biodiversity strong within the community (Preshoff, 2015).

Figure 8. Liana Vines entangled up a tree branch, supporting its foundations and assisitng in keeping it in place (Austin, 2015).

The video above will explain further on the importance of genetic diversity and cover the aspects previously explained (California Academy of Science, 2014).

In order to conserve genetics, humans have come up with a variety of strategies to help sustain the genetic diversity needed to keep ecology balanced. Examples include:

Breeding Programmes

This is where organisations, zoos and wildlife charities breed selected species to increase the overall number of the species. Usually the offspring are given as little human interaction as possible, and are intended to be released into the wild when they become independant. By housing captive bred species, these organisations are preserving the genetic material for owned species, and can selective pair suitable breeding pairs to reduce chances of inbreeding, mutations and other negative genetic transfers (Temple, 2015).

On the other hand, the factors that have reduced the population of species to begin with have not been resolved by the breeding programmes, and could potentially continue to kill off any released captives. This, and there is an overall issue of relations within zoo populus. The overall gene pool of captive animals are small, and most species are related to one another.

An example of this can be found in Yorkshire Wildlife Park, after they relocated another male Ursus Maritimus (Polar Bear) into their enclosure, only to discover accidentally that Ursus Maritimus is the grandson of the other male within the exhibit (Yorkshire WIldlife Park, 2014). This risks the possibility of accidental inbreeding happening within programmes, which could cause a variety of issues to the species.

specifically made for animals, and people walk their dogs within woodland areas, which can potentially catch and injure any wildlife (Gall, 2015). Some restrictions have been implemented within parks, however it is not always effective. It is also impossible to keep wildlife within the park; once they leave the grounds they are not protected and could get killed by other sources (Melford, 2015).

Catch and Release

This is a technique where people capture wildlife, give them an overall health check, report their information, and tag the animal before releasing it back into the wild (Seaturtle.org, 2015). Most commonly used for fish species, this technique allows us to track the location and area that species like to travel, and identify territories, bigration routes, and conflicts throughout a given area. Tracking methods include microchips, ear tags, leg rings, and tracking antennae; depending on the species depends on the method, as some techniques are invasive of the body and may not be considered meneficial to the animal (Seegar et al, 1996).

For example, Selachimorpha (sharks) would not benefit having a collar, and would instead be fitted with an antennae along the dorsal fin.

On the other hand, the stress caused to the animal could be potentially larger than first predicted. Captures don't always go smoothly, and panicked animals can hur tthemselves during an attempt to escape out of the temporary capture. There is also the worry of the tracking method becoming dislodged from the animal, or the animal stressing over the change and mutilating themselves in attempt to remove it (Florida Fish and Wildlife Conservation Commission, 2015).

Relocating Species

Relocation involves transporting an already wild animal into another wild location. This is used when introducing more species into the population in attempts to get a broader range of genetic diversity within the population gene pool. This can also be used to move a species into an environment more suited to their survival and out of the way of humans.

Although this seems approachable, there can be difficulties. Species being moved into an already existing population can result in disputes, especially if the population are not intent on adding a foreigner into their territory. Newly relocated species can be driven out of the area and back into unwanted grounds (The Humane Society of the United States, 2012). Not only this, but the specific organism being relocated needs to be appropriately tracked beforehand. There is always the risk of seperating organisms from their already existing family, which can be a hindrance if they have offspring that they are seperated from. Without their parent, offspring will be quick to die off, so research is vital before action is taken place.

Gene Banks

Gene banks are storage areas used to store genetic materials of all known organisms received within the world, collected as a copy for their DNA. Also used for plants and animals, the sole purpose of gene banks are to preserve genetic diversity (Biosciences, 2015). Gene banks are considered to be successful as they are able to conserve both plant and animal genetic resources, which can be cloned and remade into more organisms of the same standard. On the other hand, the sources of DNA stored will have to contain a variety of the same species, each specimen would need to be in no relation to the other or hold any similar traits that could become a hindrance through the copulation of offspring. Holding only one source of genetic material for a single species would not benefit its genetic diversity, as there wouldn’t be enough genetic differences to be beneficial (Engels et al, 2007).

Wildlife/Habitat Corridors

Wildlife Corridors are natural bridges built over and under main roads, used to connect wild patches of land together and allow wildlife to cross safely without having to cross the road (see figure 10). It is used to reduce the impact made from habitat fragmentation, where a large patch of habitat is congregated into separate isolated areas, usually by fences and roads (EPaRD, 2004). With smaller areas for animals to commit to territories, inbreeding and overall reduction in genetic diversity is common, and smaller animals that are likely to be killed off attempting to cross a road will be unable to resume migration tracks. With wildlife corridors present, it gives organisms the ability to travel from area to area without the risk of traffic, and encourages genetic flow of local species (Mech & Hallett, 2001). Despite this, there are negatives to the use of corridors; animals are not humans, and therefore will not always use the given corridor available. We can’t prevent them from continuing to cross traffic and reducing population numbers from road deaths, and some species may not realise that the corridor is of use to them. Not only this, but wildlife corridors are extremely tricky to make, and can be rather expensive to set up (Tran, 1997).

National Parks/Habitat Recreation

This is where a noticeable size of land has been preserved solely for wildlife. Some parks are accessable by tourists in the form of footpaths, whilst others are more recluse in private land (see figure 9). Wildlife are to be left to their own devices and undisturbed. National parks are usually funded and can come with an education programme, as well as tours depending on the size and popularity of the park (Higginbottom, 2001). Some habitats can be completely made from scratch in land bought by organisations implementing the stay of native animals.

Whilst the concept of national parks seem adequate, there are a lot of disadvantages. Allowing public access to parks cannot prevent the public from disrubting nature; children climb trees and break structures that could be

Figure 9. A sign identifying the area of land protected for wildlife (Montanarick, 2011).

Figure 10. An example of a wildlife corridor over a busy motorway (Hill, 2012).