Geographical Range Extension of the Spotfin burrfish, Chilomycterus reticulatus (L. 1758), in the Canary Islands: A Response to Ocean Warming?

Fernando Espino,Néstor E Bosch,Fernando Tuya,Josep Coca,Francisco J Otero-Ferrer,Antonio J González-Ramos,Francisco Del Rosario,Ángel C Moreno,Ricardo Haroun,Armando Del Rosario

doi:10.3390/d11120230

Abstract

In recent decades, numerous marine species have changed their distribution ranges due to ocean warming. The Spotfin burrfish, Chilomycterus reticulatus, is a reef fish with a global distribution along tropical, subtropical and warm-temperate areas of the Pacific, Indian and Atlantic oceans. In this work, we analyzed the presence of this species, between 1990 and 2019, at two islands of the Canarian Archipelago under varying oceanographic conditions: El Hierro (the westernmost island, under more tropical conditions) and Gran Canaria (a central-east island, under more cooler conditions). We expected that, under increased ocean temperatures in recent decades, the number of sightings has increased in Gran Canaria relative to El Hierro. We compiled information from different sources, including interviews and local citizenship databases. A total of 534 sightings were reported: 38.58% from El Hierro and 61.43% from Gran Canaria. The number of sightings on Gran Canaria has significantly increased through time, at a rate of 0.1 sightings per year; at El Hierro, however, the number of sightings has not significantly changed over time. Sea Surface Temperature has linearly increased in both El Hierro and Gran Canaria islands over the last three decades. Positive Sea Surface Temperature anomalies, particularly in 1998 and 2010, including high winter minimum temperatures, provide an ideal oceanographic context to favour the arrival of new individuals and, consequently, the increase in the number of sightings in Gran Canaria. Still, potential donor areas of fish recruits remain unknown.

Highlights

One of the main effects of climate change is the progressive warming of the oceans of the planet [1].This warming has resulted in an increase in average global sea surface temperatures, since the beginning of the twentieth century, of around 1 ◦ C (0.89 ◦ C in the period 1901–2012), with relevant implications for the distribution and ecology of marine species worldwide [2]
Due to increased ocean temperatures in recent decades, the number of sightings has increased in Gran Canaria relative to El Hierro
At El Hierro, C. reticulatus was observed at 38 locations (Figure 2A)

Summary

Introduction

One of the main effects of climate change is the progressive warming of the oceans of the planet [1] This warming has resulted in an increase in average global sea surface temperatures, since the beginning of the twentieth century, of around 1 ◦ C (0.89 ◦ C in the period 1901–2012), with relevant implications for the distribution and ecology of marine species worldwide [2]. Numerous marine species have changed their distribution ranges because of ocean warming [6]. For those species with large dispersion capacities, poleward range extensions, and even displacements to deeper waters, have been described [7,8]. A range of studies have shown “tropicalization” of the fish faunas from subtropical and temperate regions of the world, including an increase in the number of species of warm-water affinities; for example, the northeastern Atlantic [15], the Mediterranean Sea [16,17], the Gulf of Mexico [18] and eastern and western Australia [19,20,21]

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Results

Conclusion