This post is one of a series on projects supported by the Anderson Cabot Center’s Marine Conservation Action Fund (MCAF). Through MCAF, we support researchers, conservationists, and grassroots organizations around the world as they work to address the most challenging problems facing the oceans.
Author: Saoirse Pottie, Swansea University, Marine Megafauna Foundation
A lot has been happening both in the field and behind a computer over the last few months. The aim of this study is to collect distribution data for an endangered and noncommercial species, the zebra shark. Obtaining knowledge on the distribution of rare species is challenging, however. This information is critical to understanding potential threats and providing guidance when selecting management strategies.
Through research dives and the citizen science program “ID the Leopard Shark*” the project has now received 186 photographs and identified 89 zebra sharks in Mozambique. In addition, Mozambican researchers Cacilda da Gloria and Jorge Sitoe have conducted interviews with artisanal fishermen on zebra shark sightings and catch rates at four locations along the Mozambique coastline. In October, the preliminary results were presented at the European Elasmobranch Conference in Portugal.
In summary, interviews with fishermen proved an effective method to study the distribution of a rare, noncommercial species and when used in conjunction with citizen science could help overcome the spatial limitations of dive-based surveys. Zebra sharks in Mozambique utilize shallow, inshore waters with their range expanding southward during warmer months. One 5 kilometer reef was identified as being a potential key area, with encounter rates of zebra sharks being much higher than surrounding reefs. Over a third of zebra sharks identified (39%) at this reef were sighted again in the same location, with some individuals being sighted over eight consecutive years.
This study would not be possible without MCAF as well as the cooperation and support of the local Mozambican fishermen, researchers, dive centers, and research organizations All Out Africa, Marine Megafauna Foundation, and Zavora Marine Lab. This year will be a very exciting year. Over the next few months, the results of the study will be disseminated to the participating fishermen and the findings will be submitted for publication to the wider scientific community. The final aim is to expand the citizen science program to continue collecting data on this understudied species.
*The name zebra shark and leopard shark are used interchangeably in many parts of the world. In the United States, they are names for different species.