So... as I'm currently unemployed and looking for that first dream position I've decided to dedicate some of my time to creating some conservation fact files for some of the Earth's lesser known endangered species.
We've all heard about how the cute and cuddly Panda is threatened with extinction because of the destruction of its habitat and their specialist bamboo diet along with it. And then there's the small issue of them not liking to mate with each other AND their ability to re-absorb their foetuses when feeling stressed. All in all the Panda isn't having a great time, but awareness of this issue is high and pretty widespread.
Pretty cute right?
So here's a quick fact file to get you up to speed:
Latin Name: Pristis Pristis
Max Length: 6.5 metres
Max Weight: 1,300 pounds or 600kg
Reproduction: 5 month gestation with 1-12 young
Diet: Fish, crustaceans and molluscs.
Lifespan: Up to 80 years.
Distribution: The Freshwater Sawfish is known to occur in Northern Australia, Papua New Guinea and parts of Indonesia. But since genetic analysis bunched several species of Sawfish together as one species (the Largetooth) we now know their distribution is much greater.
A prehistoric looking creature.
The Freshwater Sawfish (now known collectively with other species as the Largetooth Sawfish) is considered to be a modified ray with a shark-like body made of cartilage, and today's modern Sawfish species (of which there are several) have been roaming the oceans and waterways for 56 million years. To put this in perspective, the ancestors of the Sawfish were evolving when Dinosaurs were walking the Earth and the modern day Sawfish appeared not long after their extinction.
The main feature of the Sawfish is its rostrum (the saw-like snout), along which there are many pairs of sharp, menacing teeth. The main question here is, how do they eat their prey if their teeth are on the outside? Well here's a short clip to answer just that....
They have been observed to use the teeth on their rostrum to spear fish so they die or become less mobile ready to be eaten, and they can do this with lightning speed.
So as an elusive fish that hunts on the river bed away from humans, how have they become critically endangered with a massively reduced population and distribution?
Well the first big one is habitat loss, a trend that is also true for many of the planet's other endangered species. Juvenile Sawfish often use shallow areas with lots of vegetation - like mangrove forests - as nursery areas, destruction and modification of these areas has led to a decline in the number of Sawfish reaching adulthood to breed.
But the most disturbing cause of their decline is perhaps their entanglement in nets, lines and trawls. Because the Sawfish has a rostrum with many sharp teeth, they often get very badly tangled in fishing nets and cannot free themselves. Fisherman also have difficulty removing them which either cannot be done or takes too long, many fisherman don't want to risk an injury from the rostrum.
So sadly what often happens is that shockingly the Sawfish have their rostrums cut off to free them from the nets. Many Sawfish will die from this mutilating injury either from the injury itself or from starvation as they no longer have the means to hunt successfully.
A Sawfish tangled in a fishing net.
A Sawfish after the removal of its rostrum.
Of course, there is also an illegal trade of Sawfish rostrums, this is a critically endangered species, so please DO NOT purchase these items.
Although Sawfish are now a protected species in many areas of the world, they are still often mutilated when they cannot be freed from fishing nets, which is just as bad as killing the animal and even worse when you consider the slow death they will have to endure. Many Sawfish habitats are now 'fishing free', but people do unfortunately continue to fish in these areas.
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