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Posted by Lauren Smith on

Egg(case) Hunting this Easter

Egg(case) Hunting this Easter

Are you heading to the beach this Easter? If so forget the chocolate eggs – shark & skate eggcases are where its at!

A small spotted catshark (Scyliorhinus canicula), on Rattray Head beach, Peterhead, UK.

Some species of sharks and skates found around the UK coastline lay eggcases, this is a method of reproduction known as ‘oviparity’. Skates will lay their eggs on the seabed, with sharks usually attaching their eggs to nearby seaweed and kelp. Once the skate or shark pup has hatched, the eggcases often wash-up on the shoreline due to rough seas, or simply as a result of tidal currents and prevailing wind directions.

Some of the eggcases we have found around the Scottish coastline, Top L-R: Flapper, Blonde, Spotted, Thornback, Cuckoo and Starry Skate. Bottom L-R: Bull Huss and Small Spotted Catshark.

The Shark Trust has a number of useful guides online for identifying and recording your eggcase finds, so check out their website for more information. And don’t forget to report your finds to them (they have an app available for this too) – adding important data to their ‘great eggcase hunt’ which is a good indicator of species and populations of skates and sharks in nearby waters. Of course we would also love to see your finds, so tag us in your finds @saltwaterlifeuk on Insta and Twitter and @sharkiologist for our Facebook Page.

Resources provided online by The Shark Trust, check out what they have by going to www.sharktrust.org

Remember to check that your eggcase is empty, if in any doubt return it to the water!

Happy Eggcase Hunting!

Posted by Lauren Smith on

Beach Cleaning

Beach Cleaning

I have been taking part in, organizing and coordinating beach cleans for over 7 years now, my actions are a direct result of what i see on a daily basis; more and more rubbish ending up around our coastline. Having spent a reasonable amount of time frequenting some of the most remote Scottish beaches and coastal areas, i simply do not remember the last time i visited a beach that was rubbish free.

Just over a month ago i held a beach clean in Ullapool, this clean was just one of the 487 beaches, rivers & lakes that were tackled as part of the Surfers Against Sewage Autumn Clean Series. This year an incredible 21,200 volunteers took part in autumn cleans across the UK, removing a staggering 35.9 tonnes of marine plastic pollution, as well as other rubbish such as metal oil drums, tin cans and car parts!

The increased awareness amongst the public led to 100 more cleans in 2018 than at the same time last year. This increase in support was mirrored by the doubling of volunteers taking part in the Marine Conservation Societies ‘Great British Beach Clean’, this year when compared to 2017.

When i first started beach cleaning the objective would be to just pick up as much as you can and get it off the beach, whilst this is still a primary focus, cleans now endeavour to document the type and size of particular items. This helps to inform governments and provide much needed data to direct policy and look at longer-term solutions within industry, manufacturing and recycling. 

A huge thankyou to everyone who took part in this years cleans, we had a truly international effort with volunteers from Canada, Lithuania & Slovenia who were visiting this area during the clean and kindly volunteered their time. As well as plenty of local support within the community here in Ullapool.

Posted by Lauren Smith on

Call of the Blue

Call of the Blue

On the 19th of November i headed down to the Natural History Museum in London, i was attending a book launch party and would be doing a Q&A session on sharks whilst there. The book by Philip Hamilton is entitled “Call of the Blue” and tells the story of positive, focused people who are working to save our oceans. Featuring incredible images captured by Philip over a 5 year period, with chapters outlining the efforts by individuals and communities to inspire and drive change.

I was absolutely honoured to be a part of this, having been contacted around 18 months ago by Tom Hooper to give an interview about my work with sharks, excerpts of which were to be featured in the book. The launch was fantastic, representatives from all sectors were present, including CEO’s from huge companies, marine charities, activists and researchers like myself. All were there to understand more about our marine environment and the threats it currently faces.

In the afternoon prior to the launch party, the head curator of the fisheries department James Maclaine, was kind enough to indulge my curiosity and gave me a behind the scenes tour of the preserved elasmobranch specimens that were kept in the archives. This was absolutely fascinating and a real treat to see the scale of the collections they had, highlights included a Greenland Shark (Somniosus microcephalis), that had washed up on the UK coastline. This species is in my opinion one of the most extraordinary sharks out there, recent research using radio carbon dating techniques have been used on the eye tissue of these sharks. Results revealed that of the sharks sampled, age ranges varied with the minimum age being AT LEAST 272 YEARS OLD! The 2 largest sharks in the study were estimated to be between 335-392 years old! 

Having recently collected a number of eggcases around the Scottish coastline, i was particularly looking forward to seeing what species of eggcases were in the NHM collection. I was not disappointed! I was delighted (and a little concerned that i would drop it) when James handed me a Chimaera eggcase collected in 1904.

Equally fascinating was the enormous Great White Shark jaw, it was donated in the 1800’s to the museum and since then there has been an enormous amount of speculation as to the size of the shark that this jaw belonged to. Some scientists believe that the shark would have been around 8m!!! The stuff dreams are made of – well my dreams at any rate!

 

Posted by Lauren Smith on

Beach cleans & shark guts… it’s all rubbish

Beach cleans & shark guts… it’s all rubbish

Alongside my work as a shark biologist, I am a volunteer for the charity Surfers Against Sewage. As part of this role I organise and participate in numerous beach cleans along the U.K. coastline, more often than not the bulk of rubbish that we remove during these cleans are plastic items. Now assuming you haven’t been marooned in outer space in recent years, you will be well aware of the mounting plastic crisis and the fact that particles of plastic can be found in just about everything, from the air we breathe to the water and food we consume.

The ingestion of plastic debris by marine animals has been documented across a variety of species

including; marine mammals, sea birds, sea turtles and some fish species. However fewer reports have described ingestion by sharks, and so for me it was a logical step to investigate whether a small shark species, commonly landed in the U.K. contained plastics. The small spotted catshark, more often referred to as the lesser spotted dogfish (cats… dogs… for the record they are catsharks, dogfish refer to another type of shark species), are often caught in bottom trawls and line gear, although technically bycatch the larger individuals are retained for human consumption, whilst the smaller ones are used for fish meal or pot bait.

I contacted a local fish merchant based in Fraserburgh on the Moray Firth Scotland, they kindly donated 20 sharks that had been captured in the North Sea and I set about investigating the contents of their gastrointestinal tracts, a polite way of saying I dug about and scrutinised their guts, recording any identifiable objects both natural and artificial.

Of the 20 sharks i sampled, all showed evidence of predation on natural prey sources prior to being trawl captured. Remains of hermit crab carapaces, squid beaks and fish bones were found. In addition to this 3 individuals were also found to contain plastic debris within their stomachs, one is a microplastic (defined as any particle less than 5mm) believed to be a micro-bead, the other two are macroplastics (>20mm); one is thought to be a broken and eroded tag and the other is composed of three fibres most likely originating as synthetic rope.

S. canicula are known to be opportunistic feeders that predate on a wide range of fauna, including shellfish, crabs, squid and small fish. It is unclear as to whether the plastics found within the stomachs of S. canicula had been ingested directly from the water column itself, or whether these items had been previously consumed by their prey. It remains unknown for now as to whether the ingestion of these plastics will negatively impact the individual sharks, however recent studies show that the potential effects on marine species from the uptake of microplastics include; reduced survival, inability to predate effectively, oxidative status and uptake of persistent organic pollutants. Current research is now investigating the effects of biomagnification and bioaccumulation of plastics and associated chemicals throughout freshwater and marine ecosystems.

S. canicula are considered an abundant shark species with an IUCN (International Union for the Conservation Nature) Red List status of “least concern”and yet with increasing environmental threats such as plastic ingestion, combined with the overfishing of other species, resulting in these sharks being used as market substitutes, it remains to be seen for how long this status will hold true.

My study reports the first evidence of plastic debris in the stomach of S. canicula, and yet I wasn’t surprised, heck I expected to find some evidence of plastics I just wasn’t sure how much. If this isn’t depressing and a sign of our times I don’t know what is. But with recent reports detailing that an estimated 75% of all the litter in our oceans is plastic, and with around 5 million tonnes of plastic waste entering the seas annually (Thompson, 2017), its no wonder I am not surprised only saddened that I am finding plastic in the guts of sharks.

What’s the link between beach cleans and shark guts?

Alongside my work as a shark biologist, I am a volunteer for the charity Surfers Against Sewage. As part of this role I organise and participate in numerous beach cleans along the U.K. coastline, more often than not the bulk of rubbish that we remove during these cleans are plastic items. Now assuming you haven’t been marooned in outer space in recent years, you will be well aware of the mounting plastic crisis and the fact that particles of plastic can be found in just about everything, from the air we breathe to the water and food we consume.

The ingestion of plastic debris by marine animals has been documented across a variety of species

including; marine mammals, sea birds, sea turtles and some fish species. However fewer reports have described ingestion by sharks, and so for me it was a logical step to investigate whether a small shark species, commonly landed in the U.K. contained plastics. The small spotted catshark, more often referred to as the lesser spotted dogfish (cats… dogs… for the record they are catsharks, dogfish refer to another type of shark species), are often caught in bottom trawls and line gear, although technically bycatch the larger individuals are retained for human consumption, whilst the smaller ones are used for fish meal or pot bait.

I contacted a local fish merchant based in Fraserburgh on the Moray Firth Scotland, they kindly donated 20 sharks that had been captured in the North Sea and I set about investigating the contents of their gastrointestinal tracts, a polite way of saying I dug about and scrutinised their guts, recording any identifiable objects both natural and artificial.

Of the 20 sharks i sampled, all showed evidence of predation on natural prey sources

prior to being trawl captured. Remains of hermit crab carapaces, squid beaks and fish bones were found. In addition to this 3 individuals were also found to contain plastic debris within their stomachs, one is a microplastic (defined as any particle less than 5mm) believed to be a micro-bead, the other two are macroplastics (>20mm); one is thought to be a broken and eroded tag and the other is composed of three fibres most likely originating as synthetic rope.

S. canicula are known to be opportunistic feeders that predate on a wide range of fauna, including shellfish, crabs, squid and small fish. It is unclear as to whether the plastics found within the stomachs of S. canicula had been ingested directly from the water column itself, or whether these items had been previously consumed by their prey. It remains unknown for now as to whether the ingestion of these plastics will negatively impact the individual sharks, however recent studies show that the potential effects on marine species from the uptake of microplastics include; reduced survival, inability to predate effectively, oxidative status and uptake of persistent organic pollutants. Current research is now investigating the effects of biomagnification and bioaccumulation of plastics and associated chemicals throughout freshwater and marine ecosystems.

S. canicula are considered an abundant shark species with an IUCN (International Union for the Conservation Nature) Red List status of “least concern”and yet with increasing environmental threats such as plastic ingestion, combined with the overfishing of other species, resulting in these sharks being used as market substitutes, it remains to be seen for how long this status will hold true.

My study reports the first evidence of plastic debris in the stomach of S. canicula, and yet I wasn’t surprised, heck I expected to find some evidence of plastics I just wasn’t sure how much. If this isn’t depressing and a sign of our times I don’t know what is. But with recent reports detailing that an estimated 75% of all the litter in our oceans is plastic, and with around 5 million tonnes of plastic waste entering the seas annually (Thompson, 2017), its no wonder I am not surprised only saddened that I am finding plastic in the guts of sharks.

Having visited 25 beaches in the past 6 months, along the U.K., French, Spanish & Portuguese coastlines and having found plastics on every single one of those beaches the consequences of our plastic mania will be felt far into the future. However the current wave of awareness about plastic pollution amongst the general public is encouraging, the more information and education that is provided via environmental charities such as Surfers Against Sewage and through TV Shows like Blue Planet 2 as well as on social media, will create positive change by allowing people not only to make more informed choices but also to lobby and campaign to bring about change, that is so desperately required.

References

Avio, C.J., Gorbi, S., Regoli, F., 2017. Plastics and microplastics in the oceans: From emerging

pollutants to emerged threats. Marine environmental research. 1-10.

Colmenero, A.I., Barria, C., Broglio, E., Garcia-Barcelona, S., 2017. Plastic debris straps on threatened blue shark Prionace glauca. Marine Pollution Bulletin. 115, 436-438.

Derraik, J.G.B., 2002. The pollution of the marine environment by plastic debris: a review. Marine

Pollution Bulletin. 44 (9), 842-852.

Mallory, M.L., 2008. Marine plastic debris in northern fulmars from the Canadian high Arctic. Marine Pollution Bulletin. 56, 1501-1504.

Putnam, A.R., Clune, A., Buksa, B., Hammer, C., VanBrockin, H., 2017. Microplastic biomagnification in Invertebrates, Fish and Cormorants in Lake Champlain. Centre for Earth and Environmental

Science. 37.

Smith, L.E., 2018. Plastic ingestion by Scyliorhinus canicula trawl captured in the North Sea. Marine Pollution Bulletin. 130. 6-7.

Thompson, R., 2017. A journey on plastic seas. Nature. 547, 278-279.

Posted by Lauren Smith on

Manta Rays and Mirrors…

Manta Rays and Mirrors…

Here I discuss research conducted by Dr Csilla Ari and Dr Dominic D’Agostino on the Giant Manta Ray. Their study provides evidence for behavioural responses in Manta’s that are known to be prerequisites for self awareness in other species. Given that Manta Ray fisheries exist globally, where does that leave us ethically?

https://www.theguardian.com/science/blog/2018/feb/27/mirrors-have-revealed-something-new-about-manta-rays-and-it-reflects-badly-on-us

 

Posted by Lauren Smith on

Octopus release goes swimmingly!

Octopus release goes swimmingly!

octopus release

After a temporary stay at Macduff Marine Aquarium, this octopus was carefully transported back to the sea so that she would have time to find a mate and complete her lifecycle.

In the video below you can find out how we came to have this fascinating animal at the aquarium. Watch her glide gently out of her high tech tupperware transport, before jetting off and immediately adapting to her natural habitat, going straight into camouflage mode amongst the kelp.

 

 

Octopus Release from bernard martin on Vimeo.