Monday, 29 September 2008

A belated update and a hard lesson

A few days ago now (27th September) we did a trawl on the Hydra Seamount between Madagascar and the southernmost islands of the Seychelles (the Farquhar Group) I mentioned in the previous post. To the left, you can see some of the catch - mainly a scorpaenid that I think is Setarches guentheri (we caught around about 200 of them), but if you look carefully, you'll see some other species. As I mentioned before, seamounts are expected to harbour unknown biodiversity, so it can be quite exciting to see what comes up. I don't think there was anything new, but one of the species didn't match what was in the book very well (the best ID I could give it was Paracallionymus costatus), so perhaps it is something new; I called it "cf. costatus" to indicate that someone should look at the specimens more carefully at a later date. It was rather a pretty fish with some surprisingly bright pink and yellow stripes on it, particularly on the head, and long filaments out of the top of its dorsal fin - many dragonets (Family Callionymidae) are very pretty fishes; they're fun to look at.

EDIT: Some of the more enthusiastic blog-watchers will have seen a long diatribe about data loss here, which I have removed. It turns out that in actual fact absolutely no data was lost, and it was a trail of bad assumptions by myself and insufficient speaking to the right people. Sometimes on a ship it just takes a while to get everything sorted out. It makes me extremely happy that we haven't lost any data and also very apologetic to those whose characters I may have maligned through the previous version of this post.

I did consider how this may make the entire cruise and the people on it look before posting, but in the heat of the moment (and I was pretty stirred up about it) I considered it (obviously retrospectively a bad call) a realistic reflection of the kind of problems one comes across on a cruise.

In my mind, the blog is supposed to be a fairly realistic visit into life on a cruise ship - and that means challenges as well as successes. I mean it as a personal account of this trip, not as an official account of the cruise (posts about lemurs, for example, have absolutely nothing to do with a cruise, yet they are interesting).

I guess that's the difference between being part of a team and being a "neutral third party". Journalists can get away with running in, writing what they see and getting out again - but if you're part of the team, you also have to consider how the other people in the team may react to what you write more than you might under other circumstances. You have to work with them again, and a ship is a very small, close-knit community!

These messages are posted by named individuals, not as an anonymous "official" account of the cruise. They're subject to errors, and are written and edited by the person that writes them, and are thus subject to that individual's foibles. For the most part, mine.

Lesson learnt? Speak to everyone, not just one person, or, even better, head to the top of the team and ask them to look into it before assuming that because team member x can't find something, it is gone and lost. Someone else may know where it is, and team member x may not have asked them.

However, I think, once stripped of the "blame", the previous message still contained some useful points for processing large trawl catches with a lot of unknown species, and I've added a couple of generally good pointers for life in general.
In any case, I would like to again apologise to everyone for that version of the post, and to note that I also felt terrible about it - I was awake at the time, and should have personally checked the trawl sheet to make sure it was being updated with the names as they were determined, which I did not do, and coincidentally, spent most of the time whilst I was writing the previous post (and a long time afterwards) kicking myself over this. I've experienced data loss before, and it's something I vowed to myself then would never happen again.

Here are some pictures of some of the things we found:

Inger-Marie Beck with Antigonia hulleyi.







The trawl had quite a few Zeiform fishes in it.

We caught 17 tinselfishes (Xenolepidichthys dalglieshi), one of two species in the Family Grammicolepididae [If I have my Latin/Greek right, a rough translation of Xenolepidichthys is "strange-scaled fish"] on this trawl - which vindicates my identification of some post-larval fisheswhich we have caught in pelagic trawls several times as being in this family; I made the ID based on the unusually elongated scales. The smallest of the specimens we caught (see left) looks similar enough to the postlarvae that we caught previously that I can see the connection quite clearly; the fish change shape fairly drastically during adulthood.

To the left, you can see the shape of the adults alongside the juvenile pictured above (lying on the somewhat larger juvenile), and to the right, a macro photo of the unusual scales.




We also caught some Zenion. They're rather small, and the definitive character, anal fin rays, was painful to count as the fins just didn't want to stay out. They don't have a common name, but I've always thought they should be called "opal fish", as the body has the most amazing opalescent reflective patches when they catch the light just right. Trying to photograph it is decidedly tricky! The picture on the left has been heavily edited to try and get the colours to come out. Below, you can see the whole fish - this picture doesn't do these creatures any justice. I imagine they are absolutely stunning when swimming around.





This fish is Zenopsis conchifer. If you look at the large version of the picture (click on it) you should be able to see the large "bucklers" (enlarged scales) along the dorsal and anal fin bases.
These fish, common to most in the Order Zeiformes, have extremely protrusible mouths. They're apparently mainly ambush predators that sneak up to prey items very slowly, undulating their dorsal and anal fins before shooting out their mouths and vacuuming the tasty morsel into their capacious maws! We caught two other zeiform species, Allocyttus verrucosus and Cyttopsis rosea.

Hydra Seamount is about here.

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