the most affected seas by the global warming and by the extreme events derived from
the current climate change. Moreover, the increases of temperatures act synergistically with other anthropogenic disturbances, which also cause mass mortalities.
Different types of professional and recreational fishing impact mainly invertebrates
on rocky bottoms (corals, bryozoans, sponges and gorgonians), whereas trawling on
soft bottoms affect sea pens, echinoderms and many other benthic animals. Coastal
degradation, biological invasions and pollution added to high temperatures and
pathogens cause serious conservation problems for marine species in the Mediterranean Sea and hamper the recovery of their populations (Lejeusne et al. 2010;
Templado 2014).
Several events of mass mortality have been detected in the Alboran Sea in recent
years, affecting different invertebrates, such as sponges, cnidarians, molluscs and
echinoderms. Maldonado et al. (2010) found disease outbreak in sponge populations
of the genus Ircinia from the Granada coast and the Chafarinas Islands and pointed
that epidemic outbreaks could recur periodically at the end of summer and early
autumn probably favoured by short periods of abnormally high water temperatures
in August. Their study in 2008 and 2009 showed that, although 27% of the sponges
died, the sponge immune system could successfully resist the disease in many cases.
More recently, in 2016 late summer, a new mass mortality event was reported for the
sponges Ircinia variabilis and Sarcotragus fasciculatus in the Granada coast coinciding with abnormally high seawater temperatures (Sánchez-Tocino and Tierno de
Figueroa 2016). In this study, diseased sponges ranged from 7.2% to 81%, and dead
ones ranged from 0% to 92.8%. Authors detected an effect of the coast topography
and thermocline position on the degree of mortality or disease, as had been previously reported for the anthozoan Corallium rubrum in the Mediterranean Sea
(Garrabou et al. 2001). Necrosis in Petrosia ficiformis related with environmental
stress was recorded in Liguria (Cerrano et al. 2001) and recently observed in Almería
(Moreno pers. obs., Fig. 10.19).
Sánchez-Tocino et al. (2017) pointed out that the moderate to low recruitment
(previously reported by Maldonado et al. 2013) of the anthozoan Ellisella
paraplexauroides populations in the Chafarinas Islands, the impacts of fishing and
the particular shallow distribution of this species in this archipelago could have an
important negative effect in its conservation. These authors also highlighted that
mass mortality events caused by high temperatures, such as those affecting other
species of gorgonians in the Mediterranean (e.g., Cerrano et al. 2000; Linares et al.
2008b; Cupido et al. 2009), could also have contributed to the preoccupying
conservation status of this population. In relation to this, de la Linde Rubio et al.
(2018) reported a mortality episode of the gorgonians Eunicella singularis and
Paramuricea clavata in Chafarinas Islands also after a high temperature event in
summer 2014. On average, 43% of the colonies of E. singularis were found dead and
21% damaged, while in P. clavata none of the studied colonies was dead but only
half of them were completely healthy. Unlike other mass mortality events in the
Mediterranean (Crisci et al. 2011), P. clavata was apparently not so affected in the
Chafarinas Islands. Nevertheless, recent observations showed mortality in the colonies of P. clavata from the shallower areas of these islands (Sánchez-Tocino et al.
412
J. Templado et al.
the current climate change. Moreover, the increases of temperatures act synergistically with other anthropogenic disturbances, which also cause mass mortalities.
Different types of professional and recreational fishing impact mainly invertebrates
on rocky bottoms (corals, bryozoans, sponges and gorgonians), whereas trawling on
soft bottoms affect sea pens, echinoderms and many other benthic animals. Coastal
degradation, biological invasions and pollution added to high temperatures and
pathogens cause serious conservation problems for marine species in the Mediterranean Sea and hamper the recovery of their populations (Lejeusne et al. 2010;
Templado 2014).
Several events of mass mortality have been detected in the Alboran Sea in recent
years, affecting different invertebrates, such as sponges, cnidarians, molluscs and
echinoderms. Maldonado et al. (2010) found disease outbreak in sponge populations
of the genus Ircinia from the Granada coast and the Chafarinas Islands and pointed
that epidemic outbreaks could recur periodically at the end of summer and early
autumn probably favoured by short periods of abnormally high water temperatures
in August. Their study in 2008 and 2009 showed that, although 27% of the sponges
died, the sponge immune system could successfully resist the disease in many cases.
More recently, in 2016 late summer, a new mass mortality event was reported for the
sponges Ircinia variabilis and Sarcotragus fasciculatus in the Granada coast coinciding with abnormally high seawater temperatures (Sánchez-Tocino and Tierno de
Figueroa 2016). In this study, diseased sponges ranged from 7.2% to 81%, and dead
ones ranged from 0% to 92.8%. Authors detected an effect of the coast topography
and thermocline position on the degree of mortality or disease, as had been previously reported for the anthozoan Corallium rubrum in the Mediterranean Sea
(Garrabou et al. 2001). Necrosis in Petrosia ficiformis related with environmental
stress was recorded in Liguria (Cerrano et al. 2001) and recently observed in Almería
(Moreno pers. obs., Fig. 10.19).
Sánchez-Tocino et al. (2017) pointed out that the moderate to low recruitment
(previously reported by Maldonado et al. 2013) of the anthozoan Ellisella
paraplexauroides populations in the Chafarinas Islands, the impacts of fishing and
the particular shallow distribution of this species in this archipelago could have an
important negative effect in its conservation. These authors also highlighted that
mass mortality events caused by high temperatures, such as those affecting other
species of gorgonians in the Mediterranean (e.g., Cerrano et al. 2000; Linares et al.
2008b; Cupido et al. 2009), could also have contributed to the preoccupying
conservation status of this population. In relation to this, de la Linde Rubio et al.
(2018) reported a mortality episode of the gorgonians Eunicella singularis and
Paramuricea clavata in Chafarinas Islands also after a high temperature event in
summer 2014. On average, 43% of the colonies of E. singularis were found dead and
21% damaged, while in P. clavata none of the studied colonies was dead but only
half of them were completely healthy. Unlike other mass mortality events in the
Mediterranean (Crisci et al. 2011), P. clavata was apparently not so affected in the
Chafarinas Islands. Nevertheless, recent observations showed mortality in the colonies of P. clavata from the shallower areas of these islands (Sánchez-Tocino et al.
412
J. Templado et al.