Flavie discusses the issue of elephant matriarch poaching, and the effect it can have on the surviving population through their ability to access resources, defend themselves appropriately and also reproduce into the future.
Image Credits: Byrdyak
Did you know that there used to be about 28 million elephants in Africa in 1800? Sadly, there were only 400,000 left in 2013. Yes, that’s insane and I’m guessing you know one of the reasons why: hunting. And the worst part is that the killing of one individual has the potential to disrupt a whole African Savanna elephant community. Let’s dive into the reasons why this is true.
First, a little bit of background information. Elephants live in matriarchies: females stick together with infants and are led by a leader called a matriarch, while adult males live on their own. There are different levels within elephant matriarchies, but one of the most basic groups is called a family unit and can contain up to 25 elephants. For simplicity, we will only talk about family units in this article.
Matriarchs are key individuals of elephant communities because groups rely on their broad ecological knowledge for decision making, as explained later on in the article. Sadly, their large size and therefore extensive tusks make them an ideal target for poaching. Historically, poachers used to primarily target mature males as they have the biggest tusks of the population, and this has led to the current bias in the number of strong mature females to males within the remaining populations. To give you an idea, the bias was assessed to have historically reached a factor of more than 50 females to 1 male in some populations. However, the rising rarity of males as a result of this targeted killing led poachers to shift from adult males to immature males and adult females – especially old matriarchs – because they are the individuals with the biggest tusks following mature males.
Image Credits: Birger Strahl
So, why is it so problematic to preferentially kill older matriarchs? As said earlier, matriarchs detain a broad ecological knowledge and therefore impact their family unit’s fitness. Following the loss of its matriarch, a group either separates or reorganises itself around a younger matriarch. In all scenarios, the group can be negatively affected in terms of resource use, defence and reproduction:
Impact on resource use
Elephants spend most of their time feeding – as they have a low digestive efficiency – which means that searching for food represents one of their biggest occupations. It is the matriarch who shapes the access to resources of her group. Indeed, the knowledge she has accumulated over the years enables her to navigate across the group’s home range to find food and water, which tend to be scattered across the area. This increased knowledge is especially valuable during dry season when resources are less readily accessible, and when members of the family are lactating or gestating.
Killing off matriarchs has therefore the potential to reduce the efficiency of elephant foraging, which could in turn negatively impact the energy reserves they use for reproduction and surviving skills such as spotting predators.
Impact on defence
Image Credits: pxhere
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