Page 16 - ARUBA TODAY

A16 LOCAL
Friday 17 January 2020
At least ten reef-associated shark species in the Dutch Caribbean

WAGENINGEN, THE NETHERLANDS showing nurse sharks. Overall, more
— Wageningen Marine Research sharks were observed in marine
reported ten reef-associated shark parks or areas of conservation than
species in the Dutch Caribbean in a in unprotected areas, highlighting
last year published study as part of the importance of these zones in
Dutch Caribbean Nature Alliance shark conservation. Furthermore,
(DCNA)’s Save Our Sharks Project. when comparing the BRUV surveys
The most common species are the from Sint Maarten, Curaçao and
nurse shark and the Caribbean Bonaire to previous BRUV studies
reef shark. Overall, more sharks from Aruba, Saba, Sint Eustatius
were observed in conservation and Saba Bank, it showed that the
areas than in unprotected areas, Aruba survey had the largest shark
highlighting the importance of diversity (8 species) and the Bonaire
these zones in shark conservation. survey the lowest (2 species). The
Saba survey documented 5 shark
More than 100 million sharks are species, Saba bank had 4 shark
killed each year as a result of species with Curaçao, Sint Eustatius
fishing and shark finning activities, and Sint Maarten each registering
twice the rate at which they can 3 shark species. There was an
reproduce. The demand for fins Caribbean reef shark in the Man of War Shoal Marine Park , Sint Maarten. additional BRUV submarine test
Photo credit: Melanie Meijer zu Schlochtern
and other shark products has at 300 metres deep off Curaçao
driven a number of species close the Dutch Postcode Lottery. In this cameras set in front of a baited which found an additional shark
to extinction. Sharks are especially project DCNA collaborated with feed bag. The idea is that as sharks species (Cuban dogfish). In total,
vulnerable to overfishing and local fisherman and scientists and come near the bait bag to feed, at least 10 shark species were seen
habitat degradation as they are aimed to build popular support video footage can be collected within the Dutch Caribbean in the
late to mature and produce few for shark and ray conservation to identify and count local shark different BRUV surveys.
young. The main threats to sharks amongst the local community, populations. The other method was
in our waters are accidental as well as increasing knowledge acoustic telemetry to track sharks. The acoustic telemetry studies
bycatch, habitat degradation about shark and ray species In this method, a small acoustic demonstrated that both the
and the risk of a shark fin market within the region by conducting a tracking device is implanted within Caribbean reef shark and nurse
developing, which would lead to number of research projects. the shark. Acoustic receivers are shark have small home ranges and
targeted fishing of sharks. installed at specific locations, strong site fidelity. Large crossings
and whenever sharks with these between areas were rare, and
We need healthy oceans and transmitters travel near the found for two Caribbean reef
healthy oceans need sharks receiver (within a range of 450 to sharks and one nurse shark which
Sharks keep our oceans healthy. 850 metres) they are recorded. travelled between Saba and
These top predators remove Saba bank. The two Caribbean
sick or weak members of their The first studies using BRUV were reef sharks made short directed
prey populations. A decrease conducted on Saba, Saba journeys back and forth, whereas
in number of sharks leads to a Bank and St. Eustatius to better the nurse shark after two years
disturbed natural balance in the understand the local population absence showed up at the Saba
sea. This can affect the overall of sharks and rays and their Bank before returning to Saba. One
fish population, and good fish relative abundances, and were nurse shark from another study on
stocks are not only important for funded by the Dutch Government. the US Virgin Islands was detected
fishermen that depend on fishing Starting in 2015, as part of the SOS in the network on the Saba Bank, a
but also for (dive) tourism and the project, additional studies were distance of at least 160 kilometres.
local community. conducted to include the waters
around Bonaire, Curaçao and Sint Importance of Protected Areas
Respect, not fear, sharks Maarten. In 2017 a BRUV survey Both the BRUV and acoustic
Sharks are some of the most was done at Aruba, financed by telemetry studies showed higher
misunderstood species. For Nurse shark on the Saba Bank which is Global Finprint. presence of reef associated sharks
generations sharks had an part of the Yarari Marine Mammal and within the conservation zones,
undeserved bad reputation. Shark Sanctuary. In addition, as part of the SOS along with high site fidelity and
Photo credit: Hans Leijnse (SHAPE/
People tend to see them as DCNA) project, acoustic telemetry was small home ranges. Furthermore, as
terrifying animals that pose a also used to better understand some longer distance movements
danger to everything that swims the movements of sharks, habitat were also documented,
in the ocean, including humans. Shark Research use, migration and connectivity interconnectivity between these
But we now know that is very far A last year published study by between islands. The telemetry areas is just beginning to be
from the truth; these magnificent Wageningen Marine Research study tracked two shark understood. The ongoing study on
creatures are essential to healthy as part of DCNA’s SOS Project species, Caribbean reef shark acoustic telemetry (funded by the
oceans and risks to humans are established a baseline for current (Carcharhinus perezi) and nurse Ministry of Agriculture, Nature and
small. shark diversity, distribution, shark (Ginglymostoma cirratum) Food Quality (LNV)) will yield more
abundance, spatial behaviour and around Saba (from 2014) and then data on this. Therefore, not only
DCNA’s Save Our Sharks Project population structure for inshore around Saba Bank, Sint Maarten are local marine parks crucial for
There is a lack of knowledge reefs around the Dutch Caribbean and Sint Eustatius (from 2015). the conservation efforts of sharks
concerning the distribution and islands. and rays, but larger conservation
abundance of shark and ray species Findings networks, such as the Yarari Marine
throughout the Dutch Caribbean. There were two methods used by In BRUVs deployed around Sint Mammal and Shark Sanctuary
To combat this knowledge gap, the researchers to study sharks. Maarten, Curaçao and Bonaire which compromises all the
from 2015-2018, DCNA ran the One method used Baited Remote the most common detected shark waters of Bonaire, Saba and Sint
“Save our Sharks” (SOS) project for Underwater Video (BRUV) which species were Caribbean reef shark, Eustatius, are vital to protect entire
the Dutch Caribbean, funded by used a device consisting of two with Sint Maarten also frequently populations.q