Sharks and sawfishes in Dakar

Sawfish rostra from the collection at Musée de la Mer

Perhaps Senegal was once a prime sawfish habitat, or perhaps the presence of the Institut Fondamentale d'Afrique Noir (IFAN) and the Musée de la Mer were hubs for the collection of sawfish rostra and other treasures from the sea. In either case, Dakar has proven a good place to search for sawfish rostra, thus far. On Tuesday, I visited the Musée de la Mer on the island of Gorée. The collection of rostra, documented in a 2006 publication on sawfishes in West Africa (Robillard & Séret 2006), were still there, albeit in a worsening state. Sadly, the museum on Gorée has been closed for several years due to lack of funding and the store room’s roof leaks, which has caused the disintegration of one rostrum. The collection includes some fascinating items and I hope there might be some way to re-house them so they can be better cared-for. 

On Wednesday, I spent a few hours sloshing through fish blood, scales and grime at the marché centrale de poissons (note: flip-flops are not recommended footwear). I'm hoping, during my field period in Senegal and The Gambia, to collect some samples of sharks and rays to contribute to the NSF Tree of Life's cartilagenous fishes project. Tiptoeing between the murky streams running over the concrete, I ducked out of the sunshine and into the shady space bustling with chatter, women sitting behind carefully arranged piles of fish, men scraping knives over silvery bodies and glittering the air around them with scales, others sweeping pools of bloody water from here to there. Nobody knew where I could find sharks.

I wandered amongst the sellers, chastising myself for not having arrived earlier, when I almost collided with a large metal trolley bearing five hammerhead sharks, at least two of which were well over a metre in length. This made a big change from Bissau's market, which I visited in 2012 and where I saw only tiny sharks, less than 40 cm long. I began chattering to the trolley-bearer but when he established that I didn’t want to buy the sharks, he was in a rush to move on. Some pleading and bargaining ensued, during which a small crowd gathered to watch, and eventually I promised to pay him 2000 CFA (about €3.50) if I could measure, photograph and sample two hammerheads.  I then had an audience while I took a small snip from the gills (the dorsal fins, and the pectorals of the larger sharks, had already been removed) and took some photographs. Having finished sampling the largest shark, the trolley-bearer’s boss appeared and started shouting in Spanish, and they made off with the sharks, leaving me without my second sample. 
 
I was beginning to feel a little self-conscious as I continued my search, and the hammerheads had obviously been a lucky find - there were no other sharks on sale. Then, as I was beginning to give up, I met Oumar. Oumar might well have been the king of the fish market. With twinkling eyes and wearing a white cotton suit jacket and matching trousers, both smeared with fish guts, and a pair of wellies, he somehow managed to look both dapper and wise. Sharks were rare, he said, but was I interested in rays? He led me to a sack full of guitarfish, and helped me to set a price so that I could measure and take samples from two of them. He gave me his number so that he could help me whenever I came back to the market. Considerably cheered, I stuffed sample tubes and data sheets and camera into my bag and stepped out into the sunlight, spattered with fish scales but feeling successful. 

IFAN has also proven an interesting source of old records of whale and dolphin strandings. In the store room there I found a collection of bleached and desiccated treasures that had been cast ashore in the past century: another sawfish rostrum, the jaws of a white shark, the dried tail of a dolphin and the caudal (tail) fin of a thresher shark, well over a metre long; a whale vertebra, dolphin skulls and jars of baby rays and a sea snake, all laid out on top of filing cabinets like some still life waiting to be captured on canvas. More dolphin skulls lined shelves reaching to the ceiling and spilled from cardboard boxes on the floor. That room alone spoke volumes about the diversity of marine life in West African waters, and the lengths gone to in the past to document that biodiversity. I hope that we can begin again to recognise the value of these waters as an important habitat for many unique and dwindling species.

I am grateful to Prof. Abdoullaye Djiba for facilitating my visits to la Musée de la Mer and IFAN, and for his ongoing collaboration. On Sunday I will escape Dakar's tangle of traffic and head south for The Gambia, to start searching for Atlantic humpback dolphins with the staff of the Niumi National Park. 

This work is being conducted in collaboration with CSIRO Marine & Atmospheric Research (Australia) and the College of Charleston (USA). The data will also be incorporated into the NSF-funded Tree of Life of cartilagenous fishes project. 

Special thanks to Nathalie Cadot and Hélène Schwartz for their hospitality during my time in Dakar.