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I came across an interesting article (by Errol Kiong) concerning the work of a zoologist and conservationist named Dr. Steve O'Shea (nased at Auckland University in New Zealand).
[url="http://www.stuff.co.nz/stuff/0,2106,2941259a7693,00.html"]http://www.stuff.co.nz/stuff/0,2106,2941259a7693,00.html[/url]
I picked up a few interesting facts:
1) Giant squid do not attack whales. Giant squid eat small fish and other squid. The female grows to a total length of 13 metres while the male reaches up to 10 metres.
2) New Zealand has 96 species of squid and 42 species of octopus in its waters, the highest diversity count in the world.
3) Five octopus species discovered in NZ in 1999 are already extinct, he says, solely because of deep sea bottom trawling.
4) A paper in 1967 found that a sperm whale's diet comprised 37 per cent of commercial fish species like orange roughy and hoki. Today, says Dr O'Shea, the whale eats almost exclusively squid, chomping down between 800 and 1000 a day because of fish scarcity.
5) If squid numbers fall then sperm whales that feed on them may be wiped out.
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Nice find Glen, that article is very interesting, but it paints a fairly grim picture for the future of giant squid, and sea life in general if we continue ecologically irresponsible fishing practices.
But this passage did make me smile......
"The mating process of the giant squid is a barbaric one, he says. The 275kg female has a 20-gram brain, while the smaller 150kg male has a 15-gram brain.
With a 15-gram brain coordinating a 1.5-metre penis, eight arms and two tentacles, it is understandable why cannibalism sometimes occurs during mating, Dr O'Shea says. "
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Good find that - interesting the number of different squid they have over there - i wonder how much differently they would taste - might be worth a trip over there one day, see how many different ones you can catch 
SA - the land of the bigger fish. The fish on the east, measure the least, but if you head west, you'll be bringing in the best!!
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Im surprised to find that sperm whales eat orange roughy...wouldnt one fish be tiny to the whale? Itd have to eat thousands. And I dont picture a massive whale chasing after these relatively small(compared to whale) fish.
OWNED.
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Interesting wee discussion that you're having here!
What wasn't mentioned in the article is that the 'loft' is also full of things like stomach contents of stranded cetaceans, the likes of the sperm whale (Physeter macrocephalus) and pygmy sperm whale (Kogia breviceps); ~ 15 samples of the former and 26 of the latter.
Toothed whales generally consume vast quantities of cephalopods - Physeter supposed to take 800-1000 per day just to sustain its bulk. There are only a few locations hwre they are known to dine on fish, and historically New Zealand wasn't considered to be one of them. The importance of the 1967 paper wherein 37% by wet weight commercial fish species was recorded from stomach contents of sperm whales harpooned in Cook Strait (the body of water that separates North from South Island's of New Zealand), hasn't really been recognised; but it is a fact, if we are to believe the earlier data (and I see no reason not to). It is also a fact that the diet of the whale in regional waters is nowadays exclusively squid. Many of these squid are now being seriously impacted by deep-sea trawl activity, bottom and mid water, adults and egg masses. Consequently what we expect to find is a change in either the size-class composition of squid in the diet of these whales (all stomach contents recovered from stranded [dead] whales over the past few decades), or a change in the relative abundances of certain species, or actual diversity of squid present in the stomach contents of these specimens [a consequence of changes in the abundance and diversity of squid species out there].
The majority of squid eaten by the whale are quite small, sometimes even less than that of earlier prey items (orange roughy), most definitely smaller than fish like ling. For every 1 giant squid that these whales eat they will eat several thousand considerably smaller squid (the giant squid, Architeuthis dux, is relatively important in the diet of the sperm whale in terms of biomass, but certainly not in numerical representation).
Nice to see I wasn't being criticised online; there have been a number of critical statements made about this press release.
Steve :geek
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Hi Steve,
Thanks for that additional information. Hope your research is going well. Are you finding that Govt agencies respond well to your warnings about stock depletion? e.g. trawling
Going slightly off-topic, can you tell what squid species recreational fisherman tend to catch in NZ?
Cheers, Glen <img src='http://www.squidfish.net/forums/public/style_emoticons/<#EMO_DIR#>/xyxthumbs.gif' class='bbc_emoticon' alt=':th' />
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Hi Glen
There is only one locally caught (recreational) squid in NZ waters - Sepioteuthis australis (Broad Squid); although S. lessoniana is reported from NZ waters, I've never seen a specimen (that's not to say that it doesn't occur here). The only other regularly encountered coastal squid species are Sepioloidea pacifica and S. new species (and neither of these is going to take a jig, being so small and effectively bottom dwelling).
If you are offshore then you will encounter (northern New Zealand waters) the ommastrephid (arrow) squid Eucleoteuthis luminosa, and throughout New Zealand waters, northern and southern, one of two Nototodarus species. The ommastrephids can be taken on jig.
It will take time to determine whether any government department or Ministry is taking notice of what has been said about squid stocks; I think they are as I do receive supportive word from a number in high places.
There are a number of papers that describe the immediate loss of squid of any impacted deep-sea environment (they simply 'up and go'), and the trawl nets do destroy the spherical or cylindrical pelagic egg masses of a number of species (for which the egg mass is described) - especially a problem if trawlers work through spawning aggregations of squid (as they do). In fact we've just published a paper on the egg mass of Nototodarus gouldi, and refer to the impact (intuitive) of trawlers nets on this structure. It's online at: [url="http://www.tonmo.com/science/public/EggmassesNototodarus.pdf"]http://www.tonmo.com/science/public/EggmassesNototodarus.pdf[/url]
Great site by the way; I have especially enjoyed reading about people's frustrations with jigs. It's this sort of honesty that you don't see online too often.
Steve
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Hi Steve,
I read through your article. Great stuff and nice photos. One thing I would like to know is how the arrow squid egg masses actually form in the first place. Do they start off attached to the sea floor (as with other squid like Sepioteuthis spp) and then drift off? Or do the egg masses form in mid water?
Amazing stuff. I encourage others to have a look at the photos in Steve's article.
Cheers, Glen <img src='http://www.squidfish.net/forums/public/style_emoticons/<#EMO_DIR#>/blueboxbullet.gif' class='bbc_emoticon' alt=':beer' />
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