Spanish coasts of the western Mediterranean (Carreras et al. 2018). It is of interest
that the first loggerhead turtle nesting site detected in the Iberian Peninsula was
found on the Andalusian coast (Tomás et al. 2008), and recently in Fuengirola
(Málaga) (Báez et al. 2020). However, there are not records of such nesting sites
on the coast of Morocco (Aksissou M., personal communication; Laurent 1990;
Báez and Bellido 2015). Nevertheless, on June 28, 2018, a female was tagged in
Valencia and monitored via satellite to a beach in Gouraya (Algeria) on July 7, 2018,
(Belda, personal communication) where it probably nested.
Loggerhead is the most abundant sea turtle species in the Alboran Sea (Valeiras
and Camiñas 2001; Camiñas 2004). In this area, loggerhead sea turtle specimens
come from the Mediterranean, Northeast American, and Cape Verde populations
(Margaritoulis et al. 2003; Monzón-Argüello et al. 2010). Adult and juvenile
loggerheads are found throughout the year in the Alboran Sea. There is a striking
difference in the adult loggerhead sex ratio in this area. Based on strandings, the ratio
of males to females is 1:172 (Bellido et al. 2015). Adults were stranded in the
Alboran Sea mainly in June and July (Báez et al. 2017). Some studies have
suggested bidirectional migration through the Strait of Gibraltar: from the Atlantic
area (Gulf of Cádiz) to the Alboran Sea from May to June and a subsequent move
from the Alboran Sea to the Balearic Sea from June to July (Camiñas and de la Serna
1995; Báez et al. 2017). The Strait of Gibraltar and the Alboran Sea connect the
western Mediterranean Sea and the Atlantic Ocean and therefore have been considered to be relevant corridors for sea turtles (Camiñas and de la Serna 1995; Báez
et al. 2017). These migrations could be affected by the North Atlantic Oscillation
(NAO) and the Sea Surface Temperature (SST) (Bellido et al. 2008a; Báez et al.
2011). The westerly winds prevailing during positive NAO phases and the subsequent delayed decrease in SST may lead to the accumulation in the Gulf of Cadiz of
turtles born in the Atlantic Ocean that are returning to the Atlantic Ocean from the
Alboran Sea. On the other hand, a sudden drop in SSTs accompanied by storms
increases the number of episodes of cold-stunned turtles in the area (Bellido et al.
2008a; Báez et al. 2011).
Revelles et al. (2007a) suggested that there was an asymmetrical size exchange of
loggerhead turtles between the Alboran Sea and the Atlantic Ocean through the
Strait of Gibraltar that was due to a physical barrier formed by the flow of surface
Atlantic waters entering the Mediterranean through the Strait of Gibraltar. Thus,
juvenile loggerheads born in the Atlantic Ocean remain in the Mediterranean until
they reach the minimum size to overcome the westward current.
Ocaña et al. (2005) and Benhardouze et al. (2008, 2012a) suggested that loggerhead could use the southern Alboran Sea as a specific foraging area due to the
abundance of Polybius henslowii (Decapoda, Brachyura). This species is also the
main prey of Caretta along the southern Portuguese continental coast
(Nicolau 2017).
According to genetic analysis, individual green turtles arriving on Spanish coasts
come from American or African populations. Carreras et al. (2014) used data on
observations of green turtle strandings in Spain. They concluded that the recent
results of mitochondrial DNA analysis suggest that the haplotypes of green turtles in
21 Marine Megafauna and Charismatic Vertebrate Species
715
that the first loggerhead turtle nesting site detected in the Iberian Peninsula was
found on the Andalusian coast (Tomás et al. 2008), and recently in Fuengirola
(Málaga) (Báez et al. 2020). However, there are not records of such nesting sites
on the coast of Morocco (Aksissou M., personal communication; Laurent 1990;
Báez and Bellido 2015). Nevertheless, on June 28, 2018, a female was tagged in
Valencia and monitored via satellite to a beach in Gouraya (Algeria) on July 7, 2018,
(Belda, personal communication) where it probably nested.
Loggerhead is the most abundant sea turtle species in the Alboran Sea (Valeiras
and Camiñas 2001; Camiñas 2004). In this area, loggerhead sea turtle specimens
come from the Mediterranean, Northeast American, and Cape Verde populations
(Margaritoulis et al. 2003; Monzón-Argüello et al. 2010). Adult and juvenile
loggerheads are found throughout the year in the Alboran Sea. There is a striking
difference in the adult loggerhead sex ratio in this area. Based on strandings, the ratio
of males to females is 1:172 (Bellido et al. 2015). Adults were stranded in the
Alboran Sea mainly in June and July (Báez et al. 2017). Some studies have
suggested bidirectional migration through the Strait of Gibraltar: from the Atlantic
area (Gulf of Cádiz) to the Alboran Sea from May to June and a subsequent move
from the Alboran Sea to the Balearic Sea from June to July (Camiñas and de la Serna
1995; Báez et al. 2017). The Strait of Gibraltar and the Alboran Sea connect the
western Mediterranean Sea and the Atlantic Ocean and therefore have been considered to be relevant corridors for sea turtles (Camiñas and de la Serna 1995; Báez
et al. 2017). These migrations could be affected by the North Atlantic Oscillation
(NAO) and the Sea Surface Temperature (SST) (Bellido et al. 2008a; Báez et al.
2011). The westerly winds prevailing during positive NAO phases and the subsequent delayed decrease in SST may lead to the accumulation in the Gulf of Cadiz of
turtles born in the Atlantic Ocean that are returning to the Atlantic Ocean from the
Alboran Sea. On the other hand, a sudden drop in SSTs accompanied by storms
increases the number of episodes of cold-stunned turtles in the area (Bellido et al.
2008a; Báez et al. 2011).
Revelles et al. (2007a) suggested that there was an asymmetrical size exchange of
loggerhead turtles between the Alboran Sea and the Atlantic Ocean through the
Strait of Gibraltar that was due to a physical barrier formed by the flow of surface
Atlantic waters entering the Mediterranean through the Strait of Gibraltar. Thus,
juvenile loggerheads born in the Atlantic Ocean remain in the Mediterranean until
they reach the minimum size to overcome the westward current.
Ocaña et al. (2005) and Benhardouze et al. (2008, 2012a) suggested that loggerhead could use the southern Alboran Sea as a specific foraging area due to the
abundance of Polybius henslowii (Decapoda, Brachyura). This species is also the
main prey of Caretta along the southern Portuguese continental coast
(Nicolau 2017).
According to genetic analysis, individual green turtles arriving on Spanish coasts
come from American or African populations. Carreras et al. (2014) used data on
observations of green turtle strandings in Spain. They concluded that the recent
results of mitochondrial DNA analysis suggest that the haplotypes of green turtles in
21 Marine Megafauna and Charismatic Vertebrate Species
715