The dangers of matriarch poaching for elephant populations

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

Targeted matriarch hunting is also detrimental for the elephants’ defence system. While healthy adult elephants do not have any predators apart from humans and sometimes groups of lions, elephant calves are vulnerable to hyenas, wild dogs and lions as well as harassers from other elephant groups. Adult elephants bunch into a protective display when faced with a potential threat, coordinated by the matriarch, putting calves in the centre of this display and adults surrounding them.

It has been shown that older matriarchs are better at discerning the level of a potential threat. For example, families with older matriarchs are more likely to turn back after hearing voices of Maasai men – who represent a threat – than Maasai boys – who rarely enter in conflict with them. Furthermore, groups with older matriarchs are less likely to bunch unnecessarily as they are better at discriminating threat levels (e.g. Maasai boys are less dangerous than Masaai men), saving energy by doing so. Thus, groups losing their older matriarch would probably spend more energy by forming unnecessary protective displays.

Impact on reproduction

Lastly, let’s talk about the impact on reproduction. Individuals within families led by older matriarchs have a higher reproductive  success than families with younger matriarchs. Reproductive success can be defined as the ‘number of offspring reaching sexual maturity’, which is important as it impacts the species’ population numbers.

A study on the severely poached population of Mikumi (Tanzania) showed that females within a group of highly related and strongly bonded individuals had a higher reproductive output. This paper also demonstrated that the presence of a matriarch impacts the quality of social bonds of other adults within her family unit – so it is plausible that matriarchs within poached populations impact the reproductive success of individuals within their group due to their effect on social bonds. Moreover, individuals within families led by older matriarchs have a higher reproductive success than families with younger matriarchs. Therefore, the loss of matriarchs, especially older ones, is likely to impact a group’s reproductive rate.

Conclusion

There are still a lot of unknown variables within the research field of elephant ecology, and as in every research field, contradictory information exists. Such an example would be the fact that despite all the information previously mentioned, a study showed in 2002 that groups with younger matriarchs only had lower survival and reproductive rates during drought periods as opposed to all year round. 

So all hope may not be lost concerning the resilience of African Savanna elephant populations, but action definitely needs to be taken to protect them. Poaching is and will always be a complex and global problem, as it is the response to world-wide demand in ivory and other elephant products. The decline of African elephants is a major conservation issue, and according to WWF, rehabilitating current populations will have little purpose if stricter law enforcement concerning poaching and fight against corruption do not become a priority.

About the Author: Flavie Ioos studied environmental biology at Cardiff University, and enjoys reading as well as writing about wildlife subjects. You can find another article written by herself for Wild magazine named ‘Why you should care about the destruction of tropical rainforests’ dating from 2018.