High-resolution 3D modelling of mangrove use by batoids in The Bahamas

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This research will provide empirical support of the functional significance of stingrays within mangrove ecosystems of The Bahamas. Furthermore, The Bahamas has committed to the ‘Caribbean 20/20 challenge’ whereby at least 20% of coastal marine environments will have national levels of protection by 2020, and so this project will serve as a conduit for augmentation into this initiative when establishing conservation goals for this country.

Stingrays (Batoidea) are the most diverse group of cartilaginous fishes and at the same time are the most endangered, with 19.9% of species listed as threatened by the IUCN Red List. They constitute a significant portion of biomass in coastal and nearshore environments, particularly in the tropics where they typically characterise fish community structure. Despite this, few data are available on the functional role and reliance of rays in vulnerable coastal ecosystems, for example, mangroves. As ‘ecosystem engineers’, rays provide modification to the physical habitat through bioturbation processes and their importance as keystone species to these environments includes structuring and regulating benthic communities. Given this, and their vulnerability to extrinsic pressures, information is urgently required for the assessment of dependence, fidelity and functional significance within mangrove environments.

In The Bahamas, mangrove ecosystems are unique in a global context since they are not protected by law. This is of great concern because currently, aggressive urbanisation of many islands is causing significant degradation of mangrove forests, with no ecological baseline for the fauna they support. Mangroves are essential habitats in the early life history of many economically important fish species and provide structural integrity to coastlines. Previous research has demonstrated significant declines in biodiversity and community structure from even partially cleared mangrove sites; therefore the ecological significance, and consequently, conservation value of mangrove ecosystems and key fauna that they support in The Bahamas, needs urgent attention.

The overall objective of this study is to create high-resolution maps and 3D models of stingray excavations in (a) impacted and (b) non-impacted mangrove environments in The Bahamas to determine variability in abundance and function across gradients of disturbance. More specifically we aim to:

1.   Quantify metrics of physical complexity using high-resolution 3D models of individual stingray excavations among locations.

2.   Determine overall abundance and physical impacts of stingrays across gradients and among locations through modeling and mapping at the individual site level.

Updates on this project can be found here and on our Instagram Page. Please contact us through our website for further information!