Page 39 - wmo-51st-magazine

Sensory adaptations further enhance
the blue marlin’s predatory abilities.
Their eyes are adapted for excellent
vision, even in the dim light of deeper
waters. This visual acuity allows them
to detect prey and navigate their en-
vironment with precision. Moreover,
the lateral line system, which detects
vibrations and pressure changes in the
water, provides additional information
about the location of prey and potential
threats.

We know that breeding

behaviour in blue marlin are

aligned with migratory habits.

Breeding behavior in blue marlins is
closely aligned with their migratory hab-
its. Spawning typically occurs in warmer
waters, where females release millions
of eggs into the water column. The lar-
vae that hatch are subject to high preda-
tion rates, but those that survive grow
rapidly, benefitting from the rich marine
environment. This reproductive strategy
ensures that blue marlins can maintain
their populations despite the challenges
of predation and environmental variabil-
ity.

The blue marlin’s status as an apex
predator does not make it invulnera-
ble. Human activities, particularly over-
fishing, pose significant threats to their
populations. Commercial longline and
purse seine fisheries often capture blue
marlins as bycatch, leading to declines
in their numbers. Overfishing of their
prey species also impacts their food
availability, adding another layer of chal-
Photograph by: Harry R. Hindmarsh
lenge. Habitat degradation and climate
change further exacerbate these issues,

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