View Full Version : New whale strandings in NZ (part III)
Steve O'Shea Feb 2nd, 2008, 06:37pm Here are a few of the pictures from two recent strandings.
The first 4 are of a small(ish) Gray's Beaked Whale that stranded just west of where we are based, in Manukau Harbour. The whale had been transported from a beach to enable us to undertake our work without being observed, for burial (off the beach) and for some other 'testing' that I'll not go into.
It was a wet and windy day; that's Emma Beatson dressed up in whites, using her new flensing knives to open the whale, and Karl McLeod from NZ's Department of Conservation helping out.
The stomach of this whale was empty. We have removed the entire alimentary tract and will shortly go through the entire intestine looking for trace remains of anything (the diet of this species is unknown). It was a rather unusual location for one of these relatively rare whales to strand, and one of 5 to do so over the past few weeks.
The knives worked a charm!
Steve O'Shea Feb 2nd, 2008, 06:43pm And these four of a sperm whale that stranded north of where we are based (about 3.5 hours away) off Hikurangi, northland east coast. We'd never done a sperm whale from this far north. Unfortunately by the time we reached the location (when we were notified) the animal was in an advanced state of decomposition.
That's the local iwi processing the whale, recovering the bone for the purposes of carving, display, spiritual and cultural values.
The stomach of this whale was empty also (other than being full of sand - this could have been a post-mortem artefact). The head was extensively scarred with Architeuthis sucker marks.
The whale was probably female, and ~ 25 feet long. There's a bit of uncertainty here as sharks had disemboweled it. We understand that it had been dead for no more than three days; this is quite remarkable given its deteriorated state.
You'll see tractors there removing the vertebrae to enable us to gain access to the stomach. Historically we'd just gone in there with our knives, cut through ribs and recovered the stomach and other tissue samples, although this process is rather destructive. We now wait for iwi to recover what they want from the carcass before we go near it. It is only right that we do so.
There are many more images of other strandings that I'll endeavour to get online shortly, including those of Emma working at a site of a recent mass stranding.
tonmo Feb 2nd, 2008, 07:09pm Wow! Thank you Steve!
Steve O'Shea Feb 14th, 2008, 05:59pm Yet another stranding yesterday, at Taupo Bay, northeastern New Zealand. Apparently 3 or 4 Gray's beaked whales stranded, but only two were secured and remained for our autopsy (photos not included). Both were female, one lactating, and ~ 4 to 4.5 metres in length. The stomach of one was ulcerated (but healed).
Below, one of the two that we examined had its jaw snapped. Apparently it was like this whilst live, so it is no post mortem artefact. Stomachs of both were effectively empty, with contents comprising very few fish otoliths (we have yet to examine them fully; this is based on observations in the field).
monty Feb 14th, 2008, 06:19pm was the snapped jaw while alive based on witness reports, or do you have some clever way to evaluate that during the necropsy?
Steve O'Shea Feb 14th, 2008, 10:03pm Eye witness accounts Mark
tonmo Feb 15th, 2008, 12:08pm That's pretty curious, I wonder what could cause that.
Steve O'Shea Feb 15th, 2008, 04:31pm Hi T. Eye witness accounts are often contradictory (the number of whales in this stranding was 3 or 4, and the length of the animals that 'escaped' was cited as ~ 3-3.5 metres [yet the mother was lactating; I would have expected them to be ~ 2 metres if so]), but they are all we have to go on. I was told that this whale had careened into the rocks and broke the jaw as a consequence, although I see in one of the earlier images that there is a wound adjacent to the breakage that appears to have healed. It is difficult to know where and when the damage occured. I couldn't see anything at the time that might indicate propeller strike (an obvious cause) - the damage was pretty localised to the wound area. The skull was removed and might be examined by the iwi; if there is any sign of healing then the whale may have had this injury for some time (although it did look recent, and would definitely have been both painful and debilitating). In retrospect I wish I had taken a swab from the wound; next time I suppose - and I'm sure that there will be a next time, not too far away.
We've done a number of these whales now, and I've not encountered anything like this before.
Steve O'Shea Feb 29th, 2008, 04:46pm Well, yesterday we attended yet another whale stranding, another female Gray's beaked whale, 4.7 metres length, north of Auckland.
This whale stranded at one location and was then hauled by trailer to another for burial. There was no obvious external sign of damage/trauma that might have led to this stranding, although the whale had had a few battles in its time and had a number of distinctive scallop-bite-shaped marks behind the dorsal fin, and one healed breakage around the jaw.
We processed the whale, and iwi recovered the skeleton. This required us to dig two pits in the dunes, 5 metres long, 1 metre deep and wide .... no digger handy this time. One pit for the skeleton, one pit for the meat, viscera and blubber. Back-breaking work; thankfully we had quite a number of hands.
The stomach contained a few nematodes and fish eye lenses, but was basically empty, as was the intestine. We'll do a more thorough examination of the stomach (which we have retained) in the not-too-distant future.
Steve O'Shea Feb 29th, 2008, 04:52pm A few more pics
dwhatley Mar 1st, 2008, 01:20am Steve,
Is beak breakage common with this unusual jaw? What, besides running aground would cause it?
tonmo Mar 1st, 2008, 07:47am Amazing pics, thanks Steve.
Jean Mar 1st, 2008, 07:04pm Hi Steve,
Isn't it a bit unusual to have so many beaked whale strandings? I was under the impression that they were rare strandings?
J
Steve O'Shea Mar 3rd, 2008, 02:44pm I'm a tad concerned about saying anything Jean ... at least until the data is on on how many have stranded historically, where and when. Three also came in on Farewell Spit just before or after Christmas, and one off Kaikoura.
It is certainly unusual for us to deal with so many of these in such a short space of time, all female, but then it is only (relatively) recently that we've expressed an interest in them.
Jean Mar 3rd, 2008, 02:51pm Thanks Steve, you just don't hear about these strandings (unless you're on Tonmo of course). I guess mass pilot whale strandings and sperm whale strandings are more newsworthy to Journalists and thus to the public :roll:
Still would be interesting to find out!
J
Steve O'Shea Mar 20th, 2008, 12:30am Just returned from another stranding, this one a male Orca ~ 5 metres long, and at least a week dead. This is my first Orca; there are better pictures on another camera (I'm afraid I didn't have mine handy at the beginning of the exercise), so I'll post those online soon. Have a ton of video this time, so if I can figure out how to post it I'll try.
Fortunately, this time we had a grader handy, so a rather substantial hole was dug for us.
Stomach, effectively empty ... except for a few (trace) fish bones.
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