Tuesday, September 18, 2007

Orca mallorcky

Uh-oh! I think there's a good chance I'm a stringer. Birds I know about... dolphins etc, maybe some more to learn :-O At least I think my Killer Whale from last week would not withstand the scrutiny of a rarities committee. At the time I was convinced, and I still can't reconcile thet bigness with anything else, but read these uncensored emails with Kevin Hepworth, one of the coordinators of the South Grampian group of the Sea Watch Foundation...

I have this basic form for simple sightings if you want to use that.
Have you more detail on the killer whale you reported? How certain are you on the id?

Thanks Kevin.
I never know what sort of level of sighting is acceptable for dolphins etc. I'd never claim a bird on the basis of the sort of 1/2 second views of bits of the back, but there doesn't seem to be a lot of alternative for land-based cetacean watching. The Killer Whale was a female type (not the classic male fin) large, fast moving, black with a greyer saddle behind the fin and a discrete large white spot on the flanks behind the fin. I'm pretty familiar with White-beaked Dolphins (although haven't seen many this summer), but this was a discrete white patch with a sharp border - no smudginess. I was pretty convinced (diagram attached (on yellow sticky note)), but since then alarm bells have been ringing. In my limited experience of Killer WHales, the white bits are difficult to see, and I normally associate seeing white bits on the roll as a feature of White-beaked. Also I have been known to make bad calls on dolphins. So I would not say it's 100% - on that sort of brief view I would never be 100% happy that what I think I saw was definitely what was actually there. If you've been seeing Killer Whales this summer i might give myself the benefit of the doubt, but if this is the only claim for the summer, I wouldn't want to add the datapoint without longer views.
Best wishes

I couldn't tell you for sure either way, but wouldn't personally accept this as a killer whale record, but know others would. I think that whilst it's difficult, there is still the need to apply some kind of rigour to sightings. I prefer cetacean or dolphin species rather than an id.
However, have included a whitebeak image for comparison if that is any use. Unfortunately, both of these species can show quite variable patterning.
There have been whitebeaks around quite a bit recently, but this would our first killer whale for this region this year, but we have had them in the past and at this time of year.

Ta for that, Kevin
I'd agree with you that this would be a non-starter as a rare bird description and I wouldn't expect it to be acceptable as a cetacean record either. At the time I was convinced on the basis that it looked very big, but I know size impressions can be very deceptive. Btw I tend to put stuff like this on my blog - would it be OK to copy these emails on and include that picture of the dolphin comparison? the website is http://proregulus.blogspot.com if you want to see what you'd be associated with!

I think you'd agree Kevin's comparison undermines my id. It's all gone a bit IBWO on me. Mmmm... you leanr something every day. I try not to, but sometimes I can't help it.

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