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14. SAND
The majority of benthic areas in Gibraltar are composed of sand. This is the most common habitat
found within Gibraltar’s territorial waters, covering most of the eastern and western sides of the Rock.
Nevertheless it is a particularly poor habitat for biodiversity, with few fish species, amongst which the most
characteristic are:
Table 16: Main fish species found over or on sandy benthic habitat.
Common Name Scientific Name
Lesser Weaver Echiichthys vipera
Greater Weaver Trachinus draco
Stargazer Uranoscopus scaber
European Anchovy Engraulis encrasicolus
European Pilchard Sardina pilchardus
Thick-lipped Grey Mullet Chelon labrosus
Bronze Bream Pagellus acarne
Black Bream Spondyliosoma cantharus
Striped Sea-bream Pagellus mormyrus
The east side was also once a rich habitat for a wide variety of molluscs that included the following
species:
Table 17: Main bivalve molluscs that are found in the east side sandy benthic habitat.
Common Name Scientific Name
Chequered Carpet Shell Tapes decussatus
Smooth Clam Callista chione
Pod Razor Shell Ensis siliqua
Wedge Shell Donax trunculus
Corruco (Esp.) Acanthocardia tuberculata
Concha de sangre (Esp.) Glycymeris insubrica
The sandy beaches at Eastern Beach, Catalan Bay and Sandy Bay are frequented by many bathers,
especially in the summer, and are of little ecological interest as a consequence.
14.1 Current Status
The habitat has deteriorated since the 1980s due mainly to excessive rake fishing for molluscs, which
has depleted most of the species that provided the La Linea mollusc fishermen with a living. Tapes decussatus,
a common item in the La Linea fish market in the early 1970s, has practically disappeared.
Acanthocardia tuberculata, once the most common mollusc in the area, which was commonly used as fishing
bait, was also depleted in the 1980s and became scarce. Mollusc fishermen then concentrated on the
Smooth Clam Callista chione, a highly regarded edible species, and by the turn of the century catches of
the species had dropped considerably, and immature specimens made up most of the numbers (pers.
obs.).
The Pod Razor Ensis siliqua survived the onslaught because of its ability to burrow quickly into the
sand, and can still be found in good numbers off Eastern Beach. The Wedge Shell Donax trunculus is
adapted to living close inshore, within 100m, and has survived until now. Nevertheless Spanish fishing
boats continue to fish inside the buoy-demarcated areas of the beaches in the early mornings and indiscriminately
rake for this species. This continues despite the Nature Protection Ordinance, 1991 which prohibits
both the use of rakes in Gibraltar territorial waters. The use of vessels within the demarcated buoyed
areas of the beaches is also forbidden (L/N 143 of 1995).
The loss of the rich mollusc breeding grounds to the east of Gibraltar has had a serious impact on the
quantity and species of fish that frequented these shores. Before the industrialisation of mollusc fishing in
the 1960s, it was commonplace to catch a large variety of fish from the shoreline using beach-casting fishing
methods. Sea Bass and Bream species of considerable size were frequent, but now it is rare to catch
a worthwhile fish of any size (pers. obs.).
Rake fishing in the area of Western Beach and the Airport during the late 1990s destroyed a sensitive
Habitats
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