Cooperative hunting

[Ben C]

Just read a paper on the cooperative nature of Harris Hawks. I know Gazman and I agreed that they probably flew in FAMILY groups. Not so, and they are not geographically specific, I.E the Sonoran desert either.

According to this paper, observed behaviour of a group during the 'breeding season' showed there are three levels of cooperative interaction. Alpha hawks, beta hawks and one gamma. Alpha's are the breeding pair the others are hunters. The Beta and Gamma are not closely related and yet they supply the Alpha hawks with prey. The clever bit is they drop it off, or pass it from up to 50 meters away.

Apparantly this may be due to the release of a hormone called 'prolactin' AFTER the eggs hatch. I thought 'prolactin' was used to produce milk in mammels.....so whats it doing in male hawks for gawwdsake????

So come on you vets, explain this in laymens terms if you will :D :D :D :D

[SparsTheOne]

it does make sense that the beta and gamma hawks are not closely related or even not related at all,because if there was any chance of one of these birds becoming an alpha hawk it would stop inbreed and create a stronger blood line for future generations.


cheers jase.

[Gaz]

Just relaying the findings of a man who has spent 28yrs of his life studying them.

[Ben C]

I am not questioning you or the man at all Gaz :) Try and find it, the title is 'Hormonal correlates of parental and helping behaviour in cooperatively breeding harris hawks (parabuteo unicinctus)' by Carol Master Vleck, Nora A Mays, James W Dawson and Arthur R Goldsmith. From an online library of scientific journals. Can't be any more specific as me girlfriend found it. I could send out hard copies if anyone is interested..PM me.

[OutFlying]

seems like light bedtime reading :lol:

[Ben C]

Here we go, have a look at this folks

http://w3.trib.com/~phxcon/HARRISHAWK_WOUNDED.html

[Wightwings]

very interesting reading thanks

[North East Harris Hawker]

i liked this bit
"We hypothesize that injured Harris' Hawks enhanced survival rate is due to their unique social attributes. Harris' Hawks live in family groups that exhibit cooperative hunting techniques, sharing food with each other in the context of a complex social order (Mader 1975; Ellis, et. al. 1993, and Bednarz 1995). Thus, we hypothesize that injured Harris' Hawks do not necessarily have to catch prey themselves. Their family group members may share food with them, thus helping to prevent severely injured Harris' Hawks from starving.

The two adult Harris' Hawks perched in the vicinity where the injured immature Harris' Hawk was trapped were most likely part of the young hawk's family group, probably her parents. We suggest the possibility that other Harris' Hawks, whether they are direct family members or socially gregarious unrelated birds, are helping severely handicapped Harris' survive in the wild in situations where other raptors would have perished due to their injuries affecting their ability to capture prey. "