Shark baselines and the conservation role of remote coral reef ecosystems

Abstract

Integrative and historical approach redefines shark baselines in remote coral reef ecosystems.

Estimating Space Use of Mobile Fishes in a Large Marine Protected Area With Methodological Considerations in Acoustic Array Design

“…However, the efficacy of any MPA is also largely dependent on effective enforcement (Edgar et al, 2014). In the case of the BIOT MPA, IUU (Ferretti et al, 2018;Tickler et al, 2019) and drifting fish aggregation devices (dFADs) (Davies et al, 2017) still pose significant management concerns within the MPA boundary.…”

“…and therefore boasts a relatively high reef fish biomass and abundance of top predators . However, the MPA has been targeted by illegal, unreported and unregulated fishing (IUU) (IOTC-2015-WPEB11-48), predominantly by vessels from India and Sri Lanka fishing for sharks (Graham et al, 2010), a problem that continues to be a significant management concern (Ferretti et al, 2018;Tickler et al, 2019).…”

Coral bleaching impacts from back-to-back 2015–2016 thermal anomalies in the remote central Indian Ocean

“…We also analyse spatial variation in coral mortality across the Archipelago primarily attributed to the 2015 and 2016 bleaching events and use remote sensing data to investigate whether coral mortality is correlated with SSTs, wave exposure, and/or plankton abundance. In the Chagos Archipelago, there is higher productivity on reefs surrounding islands with high seabird populations, whilst reefs surrounding islands with invasive rats, and hence lower seabird populations, have lower productivity (Graham et al 2018;Ferretti et al 2018). Nutrient input from seabird guano has been associated with increased plankton populations (McCauley et al 2012), which could affect coral heterotrophic feeding rates.…”

Reef Shark Science – Key Questions and Future Directions

“…Along with an improved understanding of residency patterns, Ecopath/Ecosim models can be used to estimate the carrying capacity of reef shark populations to compare to empirical data on population sizes. Defining a healthy number of reef sharks or optimal reef shark population requires understanding the carrying capacity of a reef which can only be derived from understanding the prey composition at a location, coupled with an understanding of food web dynamics, resource requirements of predators (e.g., feeding periodicity) amongst other parameters (Ferretti et al, 2018). As such, a full understanding of this question requires a number of carefully collected data sets.…”

“…The long history of human disturbance of reef ecosystems (e.g., fishing pressure, nutrient runoff) impacts our capacity to fully define the pristine condition of reefs and understand functional roles and relationships among reef-associated species (Sandin et al, 2008;Ferretti et al, 2018). This is particularly relevant for large predators (sharks and fish) that are often targets of fishing (Heupel et al, 2009;Graham et al, 2010;Ward-Paige et al, 2010;Spaet et al, 2016).…”