The famous sociobiologist, E.O. Wilson, defines biophilia as “the urge to affiliate with other forms of life.” It is this biophilia that brings me sadness when I hear that another beloved creature may soon be leaving us. I recently read an article written by Palomares, Godoy, Vincente, Rodriguesz, Roques, Casas-Marce, Revilla, and Delibes in which they explained how the Iberian Lynx might soon be leaving us. Of course, it is natural for species to come and eventually pass away with time. However, the sorrow stems from the fact that much could have been done in the past to prevent this extinction and that the initial dwindling of the population was at the fault of humans. According to the International Union for Conservation of Nature (IUCN), two populations of Iberian Lynx remain today and are found in Sierra Morena and Donana National Parks. In 1983, there were ten populations that were in need of conservation efforts, however, poaching, habitat loss, poisoning, and road casualties significantly reduced the populations of Iberian Lynx in the national parks. From 1983-2005 the percentage of lynx inside Donana National Park was reduced from 78% to 38%. The abundance of the lynx also took a critical hit in from 1989-1990 when a haemorrhagic disease wiped out a massive amount of European wild rabbits, which significantly decreased the abundance of prey available to the lynx and limiting the number of lynx breeding events. Small populations already face huge obstacles in being able to survive because they are at a much greater mercy to factors such as stochasticity (random events), genetic drift (chance genetic change), and genetic inbreeding. However, with a combination of other factors have now led these scientists to believe that the lynx is trapped in an “extinction vortex” which spells imminent demise for our furry friend.
Basically, this team of scientists gathered data on the populations of Iberian lynx for 15 years (1983-2008). They noted population sizes and their age structure, birth and death rates, and at what ages a lynx acquired territory and reproduced. They also looked at the ratio of males to females in the population, which is important because the number of reproductive females determines how many new lynx can be added to the population. Through blood and tissue samples, the scientists were also able to assess the genetic diversity amongst the population. What they found was not good for the lynx. Females were having fewer kittens and offspring survival past 3 months dropped significantly. Also, genetic diversity tests showed that heterozygosity within the population significantly decreased, which can be highly detrimental to a population for several reasons. Heterozygosity means that two alleles of a particular gene are different as opposed to the same (homozygosity). Heterozygotes typically have an advantage because they can over come harmful recessive alleles, they will have greater fitness, and they can more easily adapt to a changing environment and new biotic interactions such as parasites.
What we need to understand from this article is this: even though we may recognize the need to protect a certain species it is not always as easy as it seems to restore a population to a size where it can sustain itself. Therefore, it is important to discover which species are in need of conservation efforts as early as possible in order to aid them before it is too late. Typically the IUCN is very efficient at assessing which species are threatened or endangered, however, even in this case we see that the conservation efforts will not be enough to save the Iberian Lynx from the extinction vortex. The way in which the United States classifies endangered and threatened species is a much slower process riddled with red tape and politics. We must find a way to convince the government that this system is in need of huge repair if we are to catch these species at a population size with a large enough genetic diversity to protect their health and future success. Because telling a conservation biologist they need to save a species does no good if the species is already beyond saving. It is also necessary that humans begin to understand that they have not taken themselves out of the natural world but are still very much a part of it. We have significant impacts on the natural world and many of these impacts are extremely detrimental to the health of ecosystems, which in turn will have significant effects on our own population in the ways of global warming and resource abundances. Therefore, for the sake of our Earth, we all find our sense of biophilia and let it flourish so that we can begin to set our priorities on protecting the future of the planet and in turn ourselves.
Palomares, F., Godoy, J.A., Vincente, L., Rodriguez, A., Roques, S., Casas-Marce, M., Revilla, E., Delibes, M. 2012. Possible extinction vortex for a population of Iberian Lynx on the verge of extirpation. Conservation Biology 26: 689-697.
Picture from: http://true-wildlife.blogspot.com/2011/11/iberian-lynx.html