Fish Biodiversity of the Vitória-Trindade Seamount Chain, Southwestern Atlantic: An Updated Database

<div><p>Despite a strong increase in research on seamounts and oceanic islands ecology and biogeography, many basic aspects of their biodiversity are still unknown. In the southwestern Atlantic, the Vitória-Trindade Seamount Chain (VTC) extends ca. 1,200 km offshore the Brazilian continental shelf, from the Vitória seamount to the oceanic islands of Trindade and Martin Vaz. For a long time, most of the biological information available regarded its islands. Our study presents and analyzes an extensive database on the VTC fish biodiversity, built on data compiled from literature and recent scientific expeditions that assessed both shallow to mesophotic environments. A total of 273 species were recorded, 211 of which occur on seamounts and 173 at the islands. New records for seamounts or islands include 191 reef fish species and 64 depth range extensions. The structure of fish assemblages was similar between islands and seamounts, not differing in species geographic distribution, trophic composition, or spawning strategies. Main differences were related to endemism, higher at the islands, and to the number of endangered species, higher at the seamounts. Since unregulated fishing activities are common in the region, and mining activities are expected to drastically increase in the near future (carbonates on seamount summits and metals on slopes), this unique biodiversity needs urgent attention and management.</p></div

Summary of the fish assemblage characteristics found along the VTC.

<p>Geographic distribution (WA = Western Atlantic; TA = Trans Atlantic). Trophic guilds (CAR = carnivores; PLA = planktivores; HER = herbivores; OMN = omnivores). Spawn type (PEL = Pelagic eggs; LIV = Live birth; DEG = Demersal egg; BAL = Balistid-type demersal eggs; BRO = Brooded egg; DNP = Demersal eggs no pelagic phase). Endangered status following IUCN (CR = Critically Endangered; ED = Endangered; VU = Vulnerable; NT = Near threatened; LC = Least concern; DD = Data deficient) or Brazilian Red List (ET = Threatened of extinction; OT = Over-exploited). Habitat use (total species = proportion between the number of species that use one habitat on the total number of species found in the VTC; exclusive species = proportion between the number of species that use exclusively one habitat on the total number of species found in this habitat) (RS = reefs; RH = rhodolith beds; WC = water column; SD = sand).</p

Vitória-Trindade Chain, Southwestern Atlantic.

<p>Sites surveyed in this study are named. Bathymetric data from Smith and Sandwell [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0118180#pone.0118180.ref105" target="_blank">105</a>].</p

Diversity of habitats on the VTC.

<p>(A) rhodolith beds, extensively found on seamount summits and island’ shelves, (B) rocky reefs from Trindade and Martin Vaz islands, (C) patch reefs from Trindade Island, (D) Coralline reef structures covered of sponges at Davis Seamount; (E) High relief and complex reef structures that reaches depths of 17 m at Davis Seamount. Photos by R.M. Macieira, R. Francini-Filho, R.L. Moura, H.T. Pinheiro, PANGEA expedition.</p

Summary of sampling effort, data sources and sampling site characteristics of the Vitória-Trindade Seamount Chain, southwestern Atlantic.

<p>Type of substrate: RS—Reef structure (carbonatic); RR—Rocky reef; PR—patch reef; RH—Rhodolith bed; SD—Sand and unconsolidated substrate. Sampling techniques: DIV—Diving; ROV—Remote operated vehicle; CF—Commercial fishing; ZEE—REVIZEE scientific fishing. Primary data type: VO—Voucher specimen; PHO—photo record; VID—video record; VIS—<i>in situ</i> visual record; UVC—underwater visual census; ZEE—REVIZEE project record; OB—onboard observer record during commercial fishing.</p><p>Summary of sampling effort, data sources and sampling site characteristics of the Vitória-Trindade Seamount Chain, southwestern Atlantic.</p

Number of species recorded in each sampling site of the Vitória-Trindade Chain, southwestern Atlantic.

<p>Number of species recorded in each sampling site of the Vitória-Trindade Chain, southwestern Atlantic.</p