Wildlife Conservation and the Battle Between Paradigms

Though the world may seem scary right now, the truth is that we are living through the golden age of human existence. Modern medicine and technology have eliminated uncountable threats to humans, allowing us to flourish. Infant mortality rates globally continue to drop, from 65/1000 in 1990 to 29/1000 in 2017 according to the WHO. In that same time span the human population has increased from 5.3 billion to 7.8 billion. Yet we must ask, at what cost?

The answer is uncontrolled global warming, increased infrastructure development, and pollution, to name a few. All of these take a toll on the natural world around us, causing harm to populations of flora and fauna globally, so much so that we have started a sixth major extinction, called the Holocene extinction. 

An image of the Western Black Rhino, which went extinct in 2011 

But, that is not to say that there is not hope. Groups around the world are working to protect wildlife, hoping to save the species that we have left.

Though they work towards the same goal, there are numerous different splits among these conservation groups. One of the biggest splits is the question of whether to prioritize a few endangered species or larger numbers of less endangered species. This split has lead to two main paths of thought and theory in conservation:  the declining population paradigm and the small population paradigm. 

The declining population paradigm is associated with the lower-risk wild life that constitutes a majority. It relates to the factors that cause large populations to become small and at risk. The small population paradigm refers instead to populations that are already small (the rare and endangered species), and the factors which cause them to shrink even further. These factors are mostly stochastic (random) events. They are often referred to as 'the final nail in the coffin', because they are the factors which cause already endangered species to become extinct. In summary, the declining population paradigm would be what would put a species at risk initially, but the small population paradigm would be what effectively causes extinction. 

The Amur leopard is an example of a species affected by the small population paradigm, as the population is extremely low. It was declared critically endangered in 1996

The small population paradigm factors include two main events: random environmental events (environmental stochasticity) and random reproductive events (demographic stochasticity). Environmental stochasticity is the random fluctuation of environmental conditions, such as fires or floods, which drastically change the environment. Demographic stochasticity can be thought of as random changes in population size due to birth and death rates. For example, if during one year many more members of a particular species die than are born, the population would shrink. It also encompasses other random reproductive events such as the male to female ratio being extremely uneven. In a large population this would have a small effect, but in a small population this can be catastrophic, because there won't be enough of one of the genders to breed.

Environmental stochasticity is so detrimental to smaller populations because there is much less genetic diversity among them, so they are less adaptable to new situations. This lack of genetic diversity is an effect of the initial population loss, where the population is bottle necked. It is only further worsened by things such as genetic drift and inbreeding.

Inbreeding is particularly dangerous because of its effect on something called the extinction vortex. Unfortunately, this phenomenon is just as scary as its name makes it seem. It describes forces, like inbreeding, that cause small populations to spiral into smaller and smaller populations until eventual extinction. In Graeme Caugley's Directions in Conservation Biology he refers to the vortex as having 5 main steps:

1. As the population decreases the frequency of mating between close relatives rises
2. This leads to reduced heterozygosity in the offspring
3. This exposes more deadly recessive alleles
4. The number of offspring is lowered and mortality is increased
5. The population becomes smaller yet, and the trend may continue to extinction

A model of the extinction vortex

Declining population paradigm factors are defined as deterministic, or initial threats. These are the factors which cause a once thriving species to become dangerously small. These are factors that humans have the greatest effect on. The major deterministic threats are over harvest/hunting, habitat loss and degradation, pathogens & parasites, climate change, exotic invasive species, and pollution.

Kangaroos are considered vulnerable, which is one level up from endangered, due to hunting and habitat loss. There situation has only worsened since the Australian wildfires

Now the question for conservationists becomes: "Which paradigm should be prioritized?" If it were the small population paradigm this would mean helping species that are near extinction make a comeback. An example of this in action is the Endangered Species Act, which ensures that government agencies don't do anything to harm endangered species. Processes such as captive breeding or translocation must be put into place to help these species.

This system has worked with examples such as the Bald Eagle, California Condor, and Kirtland's Warbler.

The Kirtland Warbler hit its population low of 167 breeding pairs in 1974, but after hands on intervention it has made a huge comeback and there are now 2300 pairs. It is still listed as Critically endangered

The Bald Eagle, has made a huge recovery and is no longer listed as endangered. 

In 1987, the California Condor got a conservation plan put into action by the US government by  capturing all of the remaining Condors after their population decrease due to poaching, lead poisoning, and habitat destruction. At this time there were 27 condors. They were released back into the wild in 1991, but they are still extremely rare.

Unfortunately these processes often these do not work. As said by Audubon Researcher Joanna Grand, "It's a critical last ditch effort for species that have already experienced severe declines and occasionally it actually works...but they are really expensive and [have] a really low probability of success." 

For this reason many conservationists try to manage the bigger forces that are at work. This means working with the declining populations paradigm. In this strategy, rather than focusing on rare or endangered species, they instead focus on "keeping common animals common." This means putting into action policies to limit global warming and pollution, protecting the few remaining wild areas from development, and curbing hunting, among other things. 

In a perfect world, conservationists would have unlimited time and funds, but as it is, both are extremely limited. Unfortunately, they must make sacrifices to protect the wild life that we have left. In this case that means that we may have to sacrifice a few of the most at risk creatures to protect the majority of the others