Everyday I have been reading journal articles. Some are sent to me from my professor I will be studying with, others I just stumble upon. This one was a great find!
It is from The Auk October 2011 titled Estimating Survival and Life-Stage Transitions in the Laysan Albatross (Phoebastria immutabilis) using Multistate Mark—Recapture Models authors Eric A. VanderWerf and Lindsay C. Young. http://www.bioone.org/doi/full/10.1525/auk.2011.10285
It caught my eye because life-stage transitions is a subject I studied in school in a wildlife class, as well as something I may have to study with the Cape Vultures. It breaks up the population into different stages (ie juvenile, immature, and adult) in regards to age. And this study added another stage called skipped breeding.
Albatross nesting cycle can be so long that a breeding bird must skip the next breeding season! Hence why they added a life-stage of skipped breeding!
These birds are similar to the Cape Vultures in that they have high adult survival, low fecundity, aggregate in large groups, and are long lived. Also their main threats tend to be humans. For vultures it is collision with power lines, for albatross' it is being killed as by-catch in fishing operations. Reading about their observation techniques as well as model creation is helpful in giving me ideas with my study.
Other gems in this study included the toll on the colony during WWII. A colony on Midway Island during the war experienced a decline in the population. I hadn't thought about the causalities the earth has during human warfare.
Another gem is the high occurrence of female-female pairs in the albatross colony. The sex ratio is the colony is skewed towards females, and due to the number of potential suitors females paired with each other. Some had viable eggs due to 'extrapair copulations'. Very interesting!
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