The lesser spotted dogfish, is a very cool looking fish that can be caught in UK waters. This species is actually part of the Class Elasmobranchii, meaning its a type of shark! Dogfish however don’t get massive but that doesn’t stop then being a supercool and very elegant looking fish, despite only getting to be no more than 1mish in length.

Dogfish live sub-tidally on sand, gravel or mud beds. Their dotted pattern helps them to blend into the seafloor, when they sleep during the day. Like most sharks they nocturnally feed, so hunt during the night. Dogfish will pretty much eat any marine creature they don’t care! They can eat crustaceans, worms, small fish etc., anything small enough for it to sink its teeth into. As a result, they are a very common species to catch fishing. They are famous for still hanging around even when all the more ‘prized’ fish like bass, mackerel and cod, just can’t be caught anymore.

As this species live sub-tidally you won’t see them in rock pools unless they have been unfortunate to be washed into one as the tide recedes. But despite this they are very hardy fish, they can survive out of the water for a while! This trait even impacts how fish surveys can be carried out. For marine biologists, it is necessary to study and sample fish from the ocean, this is done by trawls of different nets for short periods of time. To reduce the likely hood of damage or death to fish more delicate and less hardy fish (like anything small and silvery) are dealt with right away.  Dogfish on the other hand are not too bothered, and are usually the last fish to be dealt with.

However, when measuring  this doesn’t mean there not a pain, literally! There skin is covered in denticles, which are hook like scales meaning there skin is very ROUGH! When you catch dogfish and need to measure them they tend to roll around your wrist and give you what I can only describe as a chinese burn with sandpaper! These little buggers can be irritating so long sleeves is super handy when dealing with them! But, as you can imagine, this is a great defence mechanisms for being attacked by a fish that is bigger and badder than them.

Lesser Spotted Dogfish Egg – Mermaids Purse

Perhaps one of the coolest things about a dogfish, and something everyone who has strolled along the beach has seen at some point is there eggs. Dogfish are oviparous, where there is internal fertilisation. This in itself is different from most marine species that just chuck all there ‘stuff’ into the water and hope fertilisation occurs and enough of there offspring survive and become reproducing adults. After internal fertilisation the mother then creates a small protective pouch where there is sufficient yolk (which acts as an energy reserve) where the small embryo will grow and after about 10 months it hatches as a 5ish cm big baby shark. This reproductive route is a lot more costly for the mother in that energy reserves must be supplied in the form of the yolks. But it is not as costly as some other shark species that are ovoviviparous, where the eggs develop inside the mother until they hatch. However, as a result the dogfish offspring have a much greater chance of survival, as their young skip the larval stage where they may be easily swallowed up and are defenceless.

Unfortunately if you have seen these eggs, which have been given the lovely name of mermaids purses, not the shore these little fellows didn’t make it. If mermaids purses become washed up from where they are  and eggs attached to the sea floor or vegetation sub tidally, then the embryos inside will die. But, on the plus side, as a way to spark interest into a young kid about marine life what better way than showing them a mermaids purse! It has a cool name with a cool story and I personally know I loved searching for these as a child.

Now onto a side note rant/ the real reason I wanted to make a post. The lesser spotted dogfish has another name, the small-spotted catshark! I have always known about this species and called it a  dogfish. was one of the many reasons I love this species. But apparently that is now not its ‘proper’ common name, and many people refer to it as a smallspotted catshark! As a dog lover, this new name infuriates me, not quite to the point when someone tries to tell me pluto is not a planet, but close! I will therefore argue this cause (until the death) to remind everyone they are DOGfish. Cat lovers already have catfish so they should leave dogfish alone! Of course this is completely useless argument because it has a latin name that won’t change,  but I just couldn’t write this post and not make my case!

Anyway, I hope next time you see a mermaids purse you will think of the DOGfish!

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