The Glue Pistons

For a long time I’ve been wanting to be involved in a recording scheme. Yet I had not quite appreciated the amount of work that is involved in managing what is often a massive collection of records. Over the past few months I’ve been collating the records of springtails (Collembola) from Surrey, which has been a big challenge, even with springtails being one of the least recorded invertebrate groups in the country.

Springtails are often tiny arthropods with six legs. Whether they’re insects or not is up to debate however. Most authorities currently class them as Entognatha, with reference to their internal mouthparts; in contrast to the external mouthparts of insects. However, the other two members of the Entognatha – Protura and Diplura – are just as closely related to springtails as they are to insects.

Another anatomical feature of springtails is the collophore located on the underside of the abdomen, after which they get their scientific name, which means ‘glue piston’. It takes the form of a tube pointing downwards from the ventral side of the first abdominal segment. Originally, it was thought to help to stabilise the animal, although it is now believed to play a part in maintaining the water content of the body.

Springtails get their common name from the furca, a long, forked organ which originates from the end of the abdomen and is often bent under the body. It is used primarily to escape predators, and can fling the springtail at incredible speeds away from danger. However, where and how the animal lands is unpredictable. Some species, such as Ceratophysella bengtssoni, have an inflatable sac on the antennae with which the springtail can adhere to the surface it lands on. Some species have only vestigial furcas or lack one entirely, often in species which live in habitats such as compact soil where the furca would inhibit the movement of the springtail, or those which live near the sea or flowing water, where an unpredictable jump could land them in an even more dangerous situation.

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Brachystomella parvula. Springtails can vary greatly in shape, this being one of the stout, pudgy Poduromorphs.

The best literature for identification is the FSC key written by the late Steve Hopkin, A Key to the Collembola (Springtails) of Britain and Ireland. This provides a complete key to all the described species thought to be present in the British Isles and is relatively recent (2007). Otherwise, there are a few good websites that can be found online, such as www.collembola.org, which has many good-quality images.

If anyone finds and identifies any springtails, I’m sure the co-ordinator of the Collembola Recording Scheme, Dr Peter Shaw, would be happy to receive any records. His details can be found here. And if anyone records any from Surrey, I’d love to hear from you so I can add the records to my growing database. You can contact me using the form under the ‘Feedback/Contact’ page on my blog. I’d also be happy to receive any unidentified specimens in need of ID.

willowsia platani 4

Willowsia platani (possibly var. nigromaculata). One of the Entomobryomorphs: comparatively long, slender springtails.

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Beluga in the Thames!

Contrary to my normal style, this blog post’s title is a little more self-explanatory than usual. This is so that when I’m scrolling through the archives in fifty years time I’ll be able to instantly recognise what this post will be about: something I’d never even considered possible.

If I was looking ahead to today from this point last week, I would probably be wondering how I’d managed to book a flight to Greenland or Svalbard at such short notice, and why it was a mild 17 degrees at such high latitudes. At the very least, I would be curious as to where I’d sourced my drugs from. I cannot believe that this morning I was enjoying a plate of chips in the warm sun at a table outside the Ship & Lobster on Mark Lane in Gravesend, Kent, while behind me a Beluga surfaced, just behind a barge with the words ‘Working for the Tidal Thames’ inscribed on its side.

The whale was first found by Dave Andrews on Tuesday, and I imagine he must have had the shock of his life when he spotted it. I certainly would have, with this record constituting one of the most southerly records of this species in the world. Belugas have a circumpolar distribution, with the nearest populations to the UK being over 2500km away. I was surprised to find out that this is the 19th sighting of Belugas in UK waters, although they have chiefly been seen in the Hebrides, Shetland and Orkney, with outlying locations being off Northumberland and Northern Ireland, both in 2015.

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The stretch of the Thames where we saw the Beluga

Belugas are interesting among whales as they can easily tolerate brackish and even freshwater. They are quite at home in estuaries and during summer often travel hundreds of kilometres up rivers in search of fish. In the remote polar regions they usually inhabit, this is fairly risk-free. The Thames is something else, however. As you can see from the above photo, residing in the Thames is not without its dangers. During the short while we were watching the sub-adult Beluga, about half-a-dozen vessels passed right over where the Beluga was seen just minutes before including a couple of massive ships.

Although, ship strikes are not the only danger this whale may have to face. There is also, of course, a higher concentration of plastic in the river than it will be used to. If it ingests too much it will die a slow and painful death. No doubt the overall relatively balmy climate will have an effect, although I’m not sure exactly how. But if Belugas weren’t affected by warm temperatures, then they wouldn’t be restricted to such icy climes.

It will be interesting to see how this Beluga’s slight wander will pan out. The best case scenario is that it will be seen swimming downstream and into the North Sea, where its instincts will kick in and it will swim back north to where it ought to be. To finish this blog post, here is a video of the couple of times I managed to record ‘Benny the Beluga’ coming up for air (email subscribers may have to click through to the blog to view the video):