INSEAD Annual Report 2023-20143 test - Flipbook - Page 33
Our Impact in 2022
Elasmobranchs displayed high variability within and
between species in their vertical movement patterns.
For example, the oceanic whitetip shark (Carcharhinus
longimanus) spent most of its time in the surface 50 m,
reef manta rays (Mobula alfredi) showed different
diving patterns in different regions whilst whale sharks
(Rhincodon typus) were the deepest diving species at
1,896 m. Substantial vertical overlap was observed for
many elasmobranchs living in the upper open ocean
(defined as sea depths down to 200 m). This increases
the likelihood these species will overlap spatially,
biologically interact, and share similar risk to threats
that vary on a vertical gradient.
This study shows the importance of incorporating
vertical as well as horizontal movement into
global management and monitoring strategies for
elasmobranchs. This includes fisheries management
and bycatch mitigation considering how these fishes
move vertically. Monitoring programmes need to
develop more affordable tags, increase geographic
coverage of studies to include developing nations, and
of underrepresented species.
Marine Science 2023
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