[MARMAM] PhD Thesis on the Fiordland Bottlenose Dolphins - alternative web address
Rohan Currey
rohan.currey at gmail.com
Mon Jan 18 22:49:18 PST 2010
Dear colleagues,
The hyperlink I posted for my thesis (see below) has stopped working.
Here is an alternative:
http://ourarchive.otago.ac.nz/handle/10523/129
If that doesn't work, please email me at:
rohan.currey at gmail.com
Best wishes,
Dr Rohan Currey
Currey, R.J.C. 2008. Conservation biology of bottlenose dolphins in
Fiordland, New Zealand. PhD Thesis, University of Otago, Dunedin, New
Zealand.
The bottlenose dolphins of Fiordland, New Zealand, live at the
southern limit of the species’ worldwide range. They are exposed to
impacts from tourism and habitat modification, particularly in
Doubtful Sound, and their conservation requirements are presently
unclear. Dolphin abundance was estimated in Doubtful Sound using
photoidentification census and capture-recapture techniques (56
individuals; 95% CI: 55-57), detecting a decline of 34-39% over 12
years among adults and sub-adults (>3 years old). The cause of this
decline was investigated via demographic modelling in Doubtful Sound
and a comparative assessment of population status in Dusky Sound.
Capture-recapture modelling of photo-identification data compiled
since 1990 yielded a constant adult survival rate marginally lower
than prior estimates for wild bottlenose dolphins (φa(1990–2008) =
0.9374; 95% CI: 0.9170-0.9530). Survival of calves (<1 year old)
declined to an unsustainable level that is thought to be the lowest
recorded for wild bottlenose dolphins (φc(2002–2008) = 0.3750; 95%
CI: 0.2080-0.5782) coincident with the opening of a second tailrace
tunnel for a hydroelectric power station. Reverse-time capture-
recapture modelling detected declines in recruitment (f(1994–2008) =
0.0249; 95% CI: 0.0174-0.0324) and population growth (λ(1994–2008)
= 0.9650; 95% CI: 0.9554-0.9746) over time consistent with the
decline in calf survival (<1 year old) and a separate reduction in
juvenile survival (1 to 3 years old) reflecting cumulative impacts.
Dolphin abundance was estimated in Dusky Sound using photo-
identification census and capture-recapture techniques (102
individuals; 95% CI: 100-104) providing no evidence of interchange
with Doubtful Sound. A comparative assessment of health status
between Doubtful and Dusky Sounds revealed skin lesioning was more
severe in Doubtful Sound, particularly among females, and newborn
calves appeared to be smaller and were born over a shorter period:
factors that may contribute to the low levels of calf survival in
Doubtful Sound. The Fiordland bottlenose dolphins were assessed under
IUCN Red List regional criteria. The small size of the population
(205 individuals; 95% CI: 192-219) combined with the projected rate
of decline in stochastic matrix models (average decline: 31.4% over
one generation) resulted in a recommended classification of
Critically Endangered.
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