One of the most threatened groups of sharks are possibly animals that you might not even know were sharks! The angel sharks (Order Squatiniformes) are very close relatives of sharks and rays, and at a glance, almost look like the evolutionary stepping stone between the two... They have flattened bodies, like their ray cousins, but also have the strong, muscular tails associated with sharks, and they are absolutely beautiful, remarkable creatures! But angel sharks are seriously threatened with extinction! So why are they declining so much? And what can we do to help them?
Angel Sharks are Becoming Increasingly Rare
Angel sharks are globally seriously at risk of extinction. The International's Union for the Conservation of Nature (IUCN), lists 50% of the 22 species as either Critically Endangered (CR), Endangered (EN) or Vulnerable (VU), which means they are at risk of being entirely wiped out globally!
Mediterranean Angel Sharks are Especially Threatened
In the Mediterranean Sea, angel sharks are particularly threatened! It is thought that population declines are as much as 90% over the past 45 years and there are now fears that angel sharks might have been so severely overexploited that they have been entirely "extirpated" from some regions (this means they have become locally extinct in certain areas of their range) (Gordon et al, 2019).
High coastal urbanisation and increasing ocean use, has damaged angel shark habitats in the Mediterranean. And, most significantly, angel sharks have been seriously overfished. They have beem targeted for meat for many generations in the Med, where they use specialised fishing gear that has designed to easily catch angel sharks in large numbers (Gordon et al, 2019).
Three species of most concern in the Med are the sawbuck angel shark (Squatina aculeata), the smooth back angel shark (Squatina oculata) and the ironically named common angel shark (Squatina squatina), all of which are categorised as Critically Endangered by the IUCN (Gordon et al, 2019).
Angel Sharks are Threatened by Overfishing & lack of Knowledge
At a glance, different species of angel sharks might look quite similar, but in fact, being able to tell them apart is one of the most important challenges for their conservation! When angel sharks are landed in fisheries they are often reported as just 'Angelsharks' or 'sand devils'. Similarly, angel sharks are referred to by many different common names, in many different languages in the Med, so it can be challenging to discern which animals fishermen are reporting in their landings figures. Therefore, it can be very difficult to track how many of each species have been fished throughout the years (Gordon et al, 2019).
Another threat facing angel sharks in the Med, is our startling lack of knowledge about them! As angel sharks are now so rare, it is very difficult to collect data about their range. This means we cannot successfully implement no-take zones to protect their critical habitats (Gordon et al, 2019).
This also means that we cannot predict how their habitat might be affected in response to climate change, so we cannot predict how this might confound their protection (Gordon et al, 2019).
Politics is Also a Threat to Mediterranean Angel Sharks
There are also multiple political and economical factors which constrain angel shark conservation in the Mediterranean (Gordon et al, 2019).
The Med is multi- jurisdictional; with more than 20 countries staking claims on the waters. This can make it difficult for the region to come to an agreement about how to protect endangered animals (Gordon et al, 2019).
Some regions are also particularly volatile and undergo regular political unrest. At best this can be a huge challenge in terms of coordinating conservation efforts between nations and at worst, this can mean conflicts between different nations can occur in response to protective measures (Gordon et al, 2019).
Many communities in the Med rely on substance fishing and therefore, there is a wide-spread culture of non-compliance with conservation legislation. Whatsmore, in the past there has been very weak implementation of protective regulations, due to limited resources and very little funding for conservation (Gordon et al, 2019).
How Can We Save Mediterranean Angel Sharks?
The IUCN Shark Specialist Group has recently produced a report about how to tackle angel shark declines and the specialist committee has come up with several goals to improve the conservation of angel sharks in the Mediterranean sea (Gordon et al, 2019).
Firstly, they discussed the importance of placing stricter controls on fisheries, which must be efficiently monitored. They suggested this could be achieved by improving public cooperation with legislation that is already in place, by improving pubic education and engagement. They advised running educational events and producing species identification guides to help fishers to understand what they may legally catch, and include training on safe-handling techniques, to ensure that fishers can release sharks with minimal stress (in order to reduce "post-release mortality") (Gordon et al, 2019).
They also discussed the need for improved data about angel sharks, which they suggested could be sourced from recreational ocean users. This would also involve public outreach, especially through angling clubs and licensing authorities, and through SCUBA groups or tourism companies. They also mentioned that collaboration with fisheries and other, separate scientific surveys could allow more data about angel shark sightings to be collected, in order to map their range and identify critical habitats. This will allow scientists to prioritise certain areas where protective measures should be implemented (Gordon et al, 2019).
They also stated that habitat degradation must be reduced to protect angel sharks, especially in their critical habitats, like feeding, mating or nursery areas. This will mean monitoring coastal developments and producing environmental impact assessments throughout the Mediterranean (Gordon et al, 2019).
This sounds like an enormous amount of work, which will involve significant financial assessment... but, don't feel overwhelmed or disheartened! There are some incredibly talented and passionate people, who are extraordinary dedicated to improving angel shark conservation measures! So we can only hope that all their hard work is fruitful and we soon see angel shark populations begin to bounce back, as these protective measures are implemented... only time will tell.
If you would like to stay up-to-date with the ongoing conservation of angel sharks, you can follow the IUCN Shark Specialist Group.
You can also join the Shark Trust, a UK based charity working towards European shark conservation through campaigning and legislation.
References
Gordon CA, Hood AR, Al Mabruk SAA, Barker J, Bartolí A., Ben Abdelhamid S, Bradai MN, Dulvy NK, Fortibuoni T, Giovos I, Jimenez Alvarado D, Meyers EKM, Morey G, Niedermuller S, Pauly A, Serena F and Vacchi M (2019). Mediterranean Angel Sharks: Regional Action Plan. The Shark Trust, United Kingdom. Access online.
By Sophie A. Maycock for SharkSpeak
it never ceases to surprise me that we have explored the moon and mars but still know so little about our oceans on earth. interesting article