Lamu: A fishing paradise

By Alex Chege, Safina Center Junior Fellow

A sea of mangrove forests flanks Kiwayu island's eastern shores. ©Alex J. Chege

I spent June to August this year visiting my research site located in the northern portion of the Lamu Archipelago in Kenya. The western part of the Indian Ocean is highly productive, and the impressive diversity of marine life in this region has led to the creation of numerous marine protected areas dotting the coasts of Eastern Africa and stretching from Mozambique to Zanzibar, Kenya, to the far-reaching corners of Somalia.

My friend Yunus uses a dhow, a traditional Swahili sailing boat, as a workbench while he demonstrates how to descale a parrotfish when there are no tools around. ©Alex J. Chege

Lamu, a town steeped in Swahili tradition and a UNESCO world heritage site is the oldest East African settlement with a nearly 700-year-old history as a cultural hub for trade and maritime activity. Off the beaten path, there are even more remote areas such as Kiwayu island, a near 3-hour speed boat from Lamu, where I did my pilot research. Kiwayu is one of few Swahili settlements located in the Kiunga Marine Reserve, making this a snorkeling and fishing paradise for the inhabitants and visitors to this part of the world. The numerous pristine islands and off shore reefs make this place a refuge for marine and terrestrial wildlife including nesting sites for five species of threatened sea turtle, dugongs, and a unique population of Vervet monkeys (Chlorocebus pygerythrus) that routinely fish for shellfish along Kiwayu’s shores.    

Exploring Fishing Traditions

“Like us humans, vervet monkeys are generalist feeders, meaning they utilize a wide range of nutritional sources and incorporate a variety of food items into their diet.” ©Alex J. Chege

Like us humans, vervet monkeys are generalist feeders, meaning they utilize a wide range of nutritional sources and incorporate a variety of food items into their diet. This high-diversity dietary strategy, also typical of other Cercopithecines (Old World Monkeys) such as baboons and macaques enable them to survive in diverse habitats and has allowed them to expand their range geographically throughout Africa, most of Asia, and in the past, Europe. However, what makes these nonhuman primates capable of living in coastal environments has rarely ever been studied.   

One morning’s haul of fish caught from within Kiwayu’s reefs. ©Alex J. Chege

My PhD research explores the general question; what makes these vervets (and humans for that matter) capable of exploiting coastal environments? And central to this is understanding the behavioural adjustments nonhuman primates make to endure dynamic coastal environments. To give an example, rising tides creates barriers to movement for vervets, fishermen and for myself when I attempt to wade between islands while holding binoculars and a notebook. Alternatively, receding tides expose new foraging opportunities in intertidal zones, with a greater abundance of easily accessible marine foods. The vervets of Kiwayu appear to take advantage of this and use this time to search, capture and feed on any clueless crabs wandering about. This behaviour appears to be learned as we watched juvenile vervets sitting on the sidelines watching the more experienced ones go first.

The African vervet monkey (Chlorocebus pygerythrus) ©Alex J. Chege

Many inhabitants of Kiwayu its neighboring islands report that this crab-eating tradition of vervet (and sometimes baboon) populations has been seen for over 30 years. And with a local selection of over 20 crab species to choose from, it’s no wonder this vervet population appears to have a developed taste for it, seemingly showing a preference for at least three different crab species.   

Kiwayu fishermen scan the reefs during low tide as they negotiate where to begin casting their net. ©Alex J. Chege

 Visiting Lamu this time around revealed some other very interesting insights. The rough waves during this monsoon season (May-July) made it impossible for fishermen to safely fish beyond the island’s reefs, yet numerous seafoods did make their way onto our plates. This season, I was lucky enough to try 11 different sea food items including fish, octopus, and of course crabs, all found from within the surrounding areas of the island. I think for humans and nonhuman primates it appears that our cultures and behaviours are deeply rooted in the environments we inhabit.

A vervet monkey forages on mangrove flowers, a preferred food item among vervets. ©Alex J. Chege