THE ULTIMATE ANGLING BUCKET LIST

Test biting then allows taste buds inside the mouth to determine whether the item in question is suitably
edible or not, which explains why surfers and swimmers attacked by sharks are often rejected. The
problem is that because of the high speed mode of attack of say a great white, the damage inflicted can
be so catastrophic that the victim bleeds to death anyway.
Sight is another sense which if the evolutionary processes that have developed it in some shark species
is anything to go by, also plays an important hunting and feeding role. But only at very close quarters
once the other senses have directed the hunt almost to the victim.
Sight generally works on the basis of incoming light being focused by a lens onto the retina at the back
of the eye, which then uses a combination of rods and cones to get the fine detail. The rods detect shades
of light and therefore movement, whereas the cones detect the fine detail and colour, which varies
species to species according to the ratio between rods and cones.
It was thought that sharks and rays could only see in black and
white, and in some cases that may well be the case. But not so
in all species. The human eye, which gives both definition and
colour, has a rods to cones ratio of four to one. Exactly the same
numbers as a great white shark. Other species however have
ratios as low as fifty to one.
Sharks and rays have another visual trick up their sleeve known
as the tapetum lucidum, which is a reflective layer of shiny cells
behind the retina for enhanced low light and nocturnal vision.
Tope eye - nictitating membrane They also have two eye lids, with those species belonging to
the requiem shark family having a third even tougher eye lid
known as a nictitating membrane. This closes upwards from the bottom to protect the eyeball when
attacking prey, something you can see in use when disgorging tope.
Arguably the most important anatomical difference between cartilaginous and bony fishes, certainly
from an angling perspective, is their breeding strategy. Sharks and rays all show clear signs of sexual
dimorphism or outward physical difference based on sex, with long thin modifications to the pelvic fins
known as clasper's in the males which are clearly missing in the females.
These are erectile and are used to transfer sperm into the female during mating, ultimately leading via
one of three different approaches to the production of low numbers of well-developed offspring.
A great survival strategy in some ways in that unlike broadcast spawner's such as cod which eject
potentially millions of eggs and sperm for external mixing, the vast majority of which won't make it
through to adulthood, the offspring survival ratio for sharks and rays can theoretically be very high,
which is great when everything is at a point of natural balance, but potentially disastrous when that isn't
the case.
The first and most primitive of these three approaches, and
the one favoured by rays and dogfishes, is oviparous
reproduction. After fertilization, the eggs are laid in horny
capsules which you often see washed up empty on the strandline
of the beach.
Another approach is viviparous reproduction resulting in the
birth of live fully formed young. Option three, which in terms
of evolutionary progress falls roughly between the other two,
is ovoviviparous reproduction, now also termed aplacental
Viable ray or dogfish egg capsules
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