Monitoring a large shark aggregation that feeds wildlife tourism

By October 2, 2017

 

Curious nurse sharks and southern stingrays dance with a snorkeler at Shark Ray Alley. Photo: Rachel Graham/MarAlliance

 

Tourism focused on encounters with sharks and rays has increased dramatically worldwide as people increasingly seek out the animals they once feared, and are keen to experience the thrill of meeting large marine wildlife up close. Successful wildlife tourism is predicated on predictability, and one way of increasing the possibility that visitors will encounter sharks and rays is by feeding the animals. This practice, also known as provisioning, has polarized biologists, who fear that feeding modifies natural behavior and also creates expectations where animals see people and expect food. There are studies that support all of these aspects, yet in countries where sharks and rays are killed, the positives of provisioning generally outweigh the negatives. Provisioning sites can help people to encounter animals that are otherwise feared and provides high non-consumptive value for sharks and rays through tourism.

The lack of information about many provisioned aggregations of sharks and rays worldwide extends to one of the longest-known provisioned sites: Shark and Ray Alley in Belize’s Hol Chan Marine Reserve.  With visitors to the marine reserve and its sharks and rays topping 75,000 people a year, the need to assess the size, demography, recruitment and diversity of species of the aggregation became the focus for our long term monitoring study. The methods are simple, consisting of weekly video and photo surveys of the individual nurse sharks (Ginglymostoma cirratum) and rays to determine whether feeding activity has affected the behaviors and habitat use of the animals at Shark Ray Alley.

Our research at Shark Ray Alley consists of individuals gathering size estimates and sexes of the sharks and rays. We also gather population counts and photo identification of the animals on site. To gather such information, we travel to Shark Ray Alley once a week with either a tour operator during their scheduled time if space is available, or with a Hol Chan Marine Reserve ranger. Upon arrival we make an initial count from the boat of the number of sharks, rays, and turtles  present. We also gather and record environmental conditions and a number of other factors including the number of guests, whether chum is used, type of chum used, and the number of other tour boats in the area. Most often we have two surveyors; one recording data and taking in water photos of individual dorsal fins, and the other using a size estimation tool with a GoPro attached recording underwater video of the animals. Here we continue the survey until the tour ends, or all of the animals vacate the area.

 

The most responsible tour operators use a chum tube stuffed with sardines and lowered to the seabed, to attract sharks and rays to their boat. Photo: Rachel Graham/MarAlliance

 

By gathering such information, we will be able to estimate average numbers of each species from the boat and in-water, average sizes, and proportions of males versus females, along with ecotourism data including average number of boats, how many tour boats feed/chum and how tour operators and tourists interact with the animals, and whether they are touching or handling the animals (which unfortunately several do).

Initial trials with a colleague’s drone highlights this as an efficient method of monitoring the provisioned aggregation from the sky. So our next step involves the purchase of a drone that will enable replicable aerial surveys to reveal abundance of animals and boats, animal behavior in relation to boats and will allow us to have a much more complete picture of the aggregation. We at MarAlliance have our very first GoFundMe campaign underway to make aerial monitoring a reality and a weekly occurrence with our surveyors. If you are keen to support our Eyes in the Sky project please visit our campaign at: https://funds.gofundme.com/dashboard/eyes-in-the-sky-to-monitor-sharks. Any size donation is most welcome.

It is clear that wherever shark and ray aggregations occur, either provisioned or natural, the sites are becoming tourism attractions. With good site management and shark and ray encounter etiquette applied by guides and rangers, such as no touching or chasing the animals, no hand feeding (use a feed tube or like), and briefing guests fully on the experience and protocol prior to entering the water, these predictable aggregations can transform a fear of sharks by many into appreciation, respect and stewardship for these magnificent creatures. And this is why we would much prefer a shark to be fed than dead.

 

A friendly Southern stingray checks out the photographer front as we take measurements to check on growth over time. Photos: Rachel Graham/MarAlliance