Friday mystery object #367 answer

Last week I gave you this rather exciting new specimen from County Kerry, Ireland to have a go at identifying:

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Perhaps unsurprisingly, it was recognised by pretty much everyone. For people based in the Americas it’s not that unusual a species and for people on the other side of the Atlantic, especially those with an interest in birds, there has been a bit of a stir in the press about this specimen.

This bird is clearly a member of the heron family – the Ardeidae – with its distinctive spear-shaped bill, relatively long legs and long and somewhat kinked neck. But it’s tiny. In fact, this is one of the smallest members of the Ardeidae, perhaps a bit longer in the body than a Dwarf Bittern, but just a bit lighter and quite different in plumage.

Dwarf Bittern in South Africa. Image by Mark Tittley, 2011

Dwarf Bittern in South Africa. Image by Mark Tittley, 2011

And this particular specimen is very light indeed. Sadly it was probably undertaking a migration south from its North American breeding grounds, when it got caught up in hurricane Lorenzo, which blew it off course, forcing it across the Atlantic Ocean, where it finally made landfall in Farranfore in County Kerry, on the west coast of Ireland on 7th October this year.

Exhausted, emaciated and severely dehydrated, the poor bird lasted less than an hour in Ireland, despite efforts to keep it going by John O’Donoghue, the owner of the garden it ended up in. John and his neighbour Anthony O’Connor recognised that it wasn’t a bird normally found in Ireland, so they got in touch with BirdWatch Ireland to find out what it was and let people know about their unfortunate visitor.

Brian Burke and colleagues from BirdWatch Ireland identified the specimen as being a Least Bittern Ixobrychus exilis (Gmelin, 1789) and they got in touch with me at the Dead Zoo about getting the specimen added to the collections, since it’s a first record of this species occurring in Ireland – and only the 10th known to have made it across the Atlantic.

Of course, I was delighted to accept on behalf of the Museum and John arranged to get the bird to me in Dublin via his local Teachta Dála (the Irish equivalent of a Member of Parliament). Now the bird is safely stowed in the Museum’s freezer awaiting assessment by a taxidermist, to see whether it’s in good enough condition to be mounted, or if I’ll need to find another way of preserving the specimen as part of the permanent collection.

If not as taxidermy, this might be as a study skin, a fluid preserved specimen or even a skeleton – each offers different information for future use. But however it gets preserved, it will provide an important physical record of an unusual visitor to the Nation for future scientists and members of the public. After all, that’s a huge part of what collections are for.

Friday mystery object #364 answer

Last week I gave you this fantastic skull from the Dead Zoo to have a go at identifying:

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It’s clearly a bird and it has a distinctive shield of keratin at the base of the bill that helps with the identification. There aren’t many birds with shields like this, although there are plenty with casques, wattles, combs and crests that need to be ruled out when thinking about possibilities.

The group that springs to my mind when it comes to facial shields like this are the Jacanas or Jesus birds, named for their apparent ability to walk on water which Wouter alluded to in the comments. Of course, they don’t actually support themselves on the surface of the water (unlike the Common Basilisk), rather they walk on vegetation at the water surface, spreading their weight across ridiculously long toes.

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Lesser Jacana, by Derek Keats, 2016

Not all Jacanas have facial shields, but there are a few that do, including the Northern Jacana Jacana spinosa (Linnaeus, 1758) that lives in South America – which is the species that this mystery skull belongs to.

The Wattled Jacana can be ruled out because it has additional drooping lobes on the lower part of the shield. There is also a Crested Jacana that looks similar to this, but the shield runs along the skull more, rather than across the front of it.

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Northern Jacana, by Benjamin Keen, 2012

The Northern Jacana also has yellow spurs on its wings that it uses for defence, which is quite distinctive. Here’s the skull back on its skeleton – you might just be able to make out those bony spurs on the wing.

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You may notice that the scientific name on this specimen label is very different to the scientific name I used – yet another example of some old taxonomy that will need updating in the collection. Some jobs are unending in museums!

Friday mystery object #363 answer

Last week I gave you this crusty critter to identify:

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It’s not the easiest mystery object, since there are around 850 species of crab, and several converge on similar forms. However, the triangular body and spindly legs meant that everyone recognised this as a species of spider crab in the Superfamily Majoidea.

Beyond that it gets harder, although there are resources out there to help. The Marine Species Identification Portal has a useful key for species that occur in the North Sea. I know that’s not always useful in these instances, but as it turns out, this particular species has a range across the East Atlantic and into the Mediterranean, including populations in the North Sea.

This little crab is Pisa armata (Latreille, 1803), which is one of several spider crabs that camouflage themselves with sessile animals and algae from their local environment, earning them the name Decorator Crabs.

Decorator crab covered in stinging hydroid polyps, which defend the crab while benefiting from food scraps and greater mobility. Image by Nick Hobgood, 2006

Decorator crab covered in stinging hydroid polyps, which defend the crab while benefiting from food scraps and greater mobility. Image by Nick Hobgood, 2006

Bit of an obscure one for you, but Diane Barlee did figure it out on Twitter, so it was manageable. Watch out for more mysteries next week!