At 12:39 17/08/2001 +1000, you wrote:
>Good evening, LK.
>
>Your observations of turkey mounds and young do not translate into an
>absence of predation. I quote from a study by Jones and Everding: "the
>large number of mounds (in some suburban areas)does not necessarily
>correlate with large numbers of recruits". They go on to state that
>hatching success from suburban mounds is lower than in wild mounds, and that
>mortality of hatchlings is high. Eggs and hatchlings are probably more
>vulnerable to predation than adults. Thus, if adults live for many years,
>it may appear as if the birds are "holding their own". If eggs are not
>hatching, or if there is little recruitment of new birds because young are
>taken before they mature, older birds may persist for years, then suddenly,
>populations may disappear as old birds die. The study lists a number of
>populations in urbanised areas of Brisbane that have disappeared
Hi everyone
I'll wade into this with my subjective observations from Moorooka, backing
on to Toohey Forest (Toohey "Mountain" side).
1. Toohey is an isolated patch of forest, surrounded by suburbia.
There is unlikely to be immigration from BFP. We have kept records at our house
for 15 years, no turkeys in the first 10 or so, now quite common. We suspect
they have come in from "dumped" birds.
2. We have a mound in our garden which has regularly produced 3-4 +?? young
a year,
its very hard to be sure because they are quite cryptic. We do see immature
birds around after the breeding season. There are other mounds up the valley.
3. I couldn't start to estimate mortality but predation is NOT the only factor.
I think the limits of food resources in suburban gardens may often be reached.
Last year in the dry spell the birds were VERY hungry, digging out all manner
of my plants, It hasn't been as bad this year.
The real effects of both predation and limiting reources are very hard to
measure.
I think that its easy just to put the blame on obvious and visible potential
predators like the cats and dogs (and the much less visible foxes) but what role
does lack of food play? I think that there is just speculation, no hard
facts on this.
4. There is no doubt numbers in our valley have increased over the past 5 years,
recruitment or release (who knows) but they seem to be holding their own against
cats, dogs and foxes.
Cheers
Pete
Dr Peter Woodall email =
Division of Vet Pathology & Anatomy
School of Veterinary Science. Phone = +61 7 3365 2300
The University of Queensland Fax = +61 7 3365 1355
Brisbane, Qld, Australia 4072 WWW = http://www.uq.edu.au/~anpwooda
"hamba phezulu" (= "go higher" in isiZulu)
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