21.6.1 Marine Mammal Tagging Studies
The number of studies using electronic tags are scarce due to the difficulties involved
in safely equipping small cetaceans with such devices (Balmer et al. 2014). Electronic tags are mainly used on large whales (Irvine et al., 2017; Lagerquist et al.
2008). Fin whales (Balaenoptera physalus) are the largest marine mammals in the
Mediterranean. One study showed that seven fin whales, which were tagged with
electronic archival tags off the Provençal coast, remained in the north-western
Mediterranean Sea for 9 months (mainly fall and winter) to forage. Of these whales,
only one migrated from the Mediterranean Sea to the Atlantic without staying in the
Alboran Sea (Bentaleb et al. 2011). To the best of our knowledge, there are no
studies using telemetry to track cetaceans in the Alboran Sea.
21.6.2 Sea Turtle Tagging Studies
Sea turtles are tagged to recognise individuals or a cohort for population research
purposes. Tag recapture is one of the methods used to estimate abundance in
migrating populations. Tagging is also conducted to obtain information on aspects
such as reproductive biology, migration, or areas of residence or foraging and to
calculate growth rates by age or by population. It is difficult to tag turtles during their
marine life-phase, and it is also difficult to gain access to fishing or sports vessels that
can catch turtles. Thus, the application of easily identifiable tags from fishing vessels
is an area of particular scientific interest.
Conventional flipper tagging and satellite tagging studies have provided information on many aspects related to the behaviour of different marine turtle species,
such as the relative importance to loggerhead turtles of neritic zones, as well as other
areas on the western Mediterranean Spanish continental shelf (Cardona et al. 2009;
Doménech et al. 2015) and by the Balearic Islands (Carreras et al. 2004). A
component of homing behaviour is the fidelity of adult loggerhead turtles to breeding
sites, which has been demonstrated by the use of genetic data to determine
metapopulation structures as well as by direct observations through flipper and
satellite tagging (Broderick et al. 2003; Casale et al. 2013; Schofield et al. 2013).
Tagging has also revealed the limited exchange of immature loggerheads between
regions in the western Mediterranean (Revelles et al. 2008). Loggerhead, green, and
leatherback turtles are the main sea turtle species in the Mediterranean. Tagging has
provided important insights into their migration (Luschi and Casale 2014) and, in the
case of loggerheads, their genetic structuring (Revelles et al. 2007a, b) and distribution (Casale et al. 2007; Revelles et al. 2008).
An external tag is typically fixed to the proximal front flipper, where it does not
hinder swimming or flipper movements. A single tag or one tag per flipper can be
applied. Two tags are used to check the percentage of tag loss (further information on
sea turtle tagging can be found in Balazs (2000)). To reduce possible injury, tags are
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J. C. Báez et al.
The number of studies using electronic tags are scarce due to the difficulties involved
in safely equipping small cetaceans with such devices (Balmer et al. 2014). Electronic tags are mainly used on large whales (Irvine et al., 2017; Lagerquist et al.
2008). Fin whales (Balaenoptera physalus) are the largest marine mammals in the
Mediterranean. One study showed that seven fin whales, which were tagged with
electronic archival tags off the Provençal coast, remained in the north-western
Mediterranean Sea for 9 months (mainly fall and winter) to forage. Of these whales,
only one migrated from the Mediterranean Sea to the Atlantic without staying in the
Alboran Sea (Bentaleb et al. 2011). To the best of our knowledge, there are no
studies using telemetry to track cetaceans in the Alboran Sea.
21.6.2 Sea Turtle Tagging Studies
Sea turtles are tagged to recognise individuals or a cohort for population research
purposes. Tag recapture is one of the methods used to estimate abundance in
migrating populations. Tagging is also conducted to obtain information on aspects
such as reproductive biology, migration, or areas of residence or foraging and to
calculate growth rates by age or by population. It is difficult to tag turtles during their
marine life-phase, and it is also difficult to gain access to fishing or sports vessels that
can catch turtles. Thus, the application of easily identifiable tags from fishing vessels
is an area of particular scientific interest.
Conventional flipper tagging and satellite tagging studies have provided information on many aspects related to the behaviour of different marine turtle species,
such as the relative importance to loggerhead turtles of neritic zones, as well as other
areas on the western Mediterranean Spanish continental shelf (Cardona et al. 2009;
Doménech et al. 2015) and by the Balearic Islands (Carreras et al. 2004). A
component of homing behaviour is the fidelity of adult loggerhead turtles to breeding
sites, which has been demonstrated by the use of genetic data to determine
metapopulation structures as well as by direct observations through flipper and
satellite tagging (Broderick et al. 2003; Casale et al. 2013; Schofield et al. 2013).
Tagging has also revealed the limited exchange of immature loggerheads between
regions in the western Mediterranean (Revelles et al. 2008). Loggerhead, green, and
leatherback turtles are the main sea turtle species in the Mediterranean. Tagging has
provided important insights into their migration (Luschi and Casale 2014) and, in the
case of loggerheads, their genetic structuring (Revelles et al. 2007a, b) and distribution (Casale et al. 2007; Revelles et al. 2008).
An external tag is typically fixed to the proximal front flipper, where it does not
hinder swimming or flipper movements. A single tag or one tag per flipper can be
applied. Two tags are used to check the percentage of tag loss (further information on
sea turtle tagging can be found in Balazs (2000)). To reduce possible injury, tags are
730
J. C. Báez et al.