stupid appearance’. Whilst they may have a face that
only a mother could love, anything that these creatures
lack in good looks, they well and truly make up for in
their incredible adaptations and abilities.
Marine Iguanas typically live
in colonies and vary
considerably in appearance
according to locality, with
the latest taxonomic revision
recognising 11 subspecies.
Maximum size ranges from a
total length of as little as
roughly 30cm to more than
130cm, with a weight range
of 1-12kg. Females are a uniform dark grey in colour, but
breeding males (which are also substantially larger than
females) may exhibit bright pink or bluish markings, or
more subtle shades of yellow, green or grey. Marine
Iguanas feed almost exclusively on algae and seaweed,
and specialisations for this lifestyle include a flattened
tail for swimming, a blunt nose that assists in grazing on
rocks, and powerful limbs and claws that help prevent the
animals from being swept away in currents. Large males
can dive to depths of up to 30m and hold their breath for
45 minutes or more, while juveniles and females forage
primarily in the shallow intertidal zones. In order to
excrete the high levels of salt consumed in their diet,
Marine Iguanas ‘sneeze’ frequently, blowing a concen-
trated salt solution from a
gland near their nostrils.
Anything these creatures
lack in good looks, they
make up for in their
incredible adaptations.
The waters around the
Galapagos are quite cold, so
when they are not at sea
searching for food, Marine
Iguanas are obliged to bask
in order to raise their body
temperature. During the day
they are a common sight basking in large numbers along
the iconic black lava coastlines, and at night they
conserve heat by huddling together in groups. They are
vulnerable whilst in the open, and are sometimes preyed
upon by the Galapagos Hawk. In response to this threat,
the iguanas have learnt to associate the warning call of
mockingbirds with the approach of a predator. When this
distinct call is heard, the iguanas can be seen running for
cover beneath rocks or shrubs. I never tired of watching