Sunday, October 14, 2007


It seems like the last few days have been rather busy, but in reality it was Saturdays non-stop schedule ( meeting, dance class, radio station, meeting, airport) that has colored my reflections about Thursday through Saturday.
Kevin White and Jamie Womble flew over from Juneau Thursday afternoon. Kevin has been with the ADF&G since 1999 working in the interior until 2001 when he moved to Juneau. Jamie is a park service biologist working in Glacier Bay on harbor seals. They are both very interesting, pleasant and easy-going people to be around. The fringe benefit of arranging the seminars and housing people is that I get alot more out of each speaker than just an 1.5 hour talk.
Kevin's talk focused on his research on the mtn. goats of Lynn Canal. The money is available for studying the animals there because of potential impacts of the road from Juneau and the Kensington mine. It makes one hope that the goats on Baranof won't receive such an intensive study. Kevin estimated that it costs about $5,000. per goat for the intial collaring. I may have my figures slightly off, but I believe that they have about 60 or so mtn goats fitted with radio collars in three study areas in Lynn Canal. One area is near Berner's Bay and the other two northward along the coast. Some goals of the study is to learn about the home range of the goats , where the critical winter habitat is located and to get additional information about some population parameters e.g. reproductive rates and mortality. We learned how to distinguish a female from a male mtn goat from a distance. Males have horns with wide base and females have a narrow base and the tips of the horns curve back rather abruptly. Mortality rates are what you would expect, males don't tend to make it through the winter as often as females because of body fat loss due to the rut. The males cover alot of ground during the rut presumably looking for females in estrus, whereas the females tended to have a smaller range during this period. The GPS derived lines on the hill side for six goats during the rut showed this rather clearly. There was this tidy little group of females hanging out eating and another set of lines representing the highly mobile males. I suppose that there is a balance between mating opportunity and not running off all of ones reserves that is selected for in mountain goats. Females don't have young until their 3rd or 4th year and continue having kids until they die. The growth rings on the horns aren't very accurate after year nine, so goats are designated 9+ after that point. Apparently twins are quite rare.
The winter diet was rather interesting mostly conifers (70%) with the rest lichens, moss, forbs and shrubs. I did find a paper on the winter forage of goats on the Cleveland peninsula. They found that conifers, lobaria, Hylocomium and Rhytidiadelphus made up the bulk of the pellet contents (I believe that this was the study Kevin was citing). Shrubs were the least common. Digestibility must influence detectability of the food, so I wonder if the results could be rather off. It does make sense that the conifers and arboreal lichens are the most accessible in the winter habitat (around 500 ft), since the snow is often covered with lichens from wind and the lower branches would be reachable. I think that if a goat can reach Hylocomium it can get forbs and shrubs as well. Kevin didn't have results from summer forage pellet analysis, he did say that he lacked a good plant species list for his study areas. I volunteered to go along next summer and create one for him (such a sacrifice!). I also volunteered for the early spring moose exclosure studies in Gustavus. If I'm returning to my mycorrhizal work I might as well return to my earlier volunteer botanist habits. I looked at my field notebook from Lynn Canal, it is a little sparse, but interesting. Considering my emotional state that summer it is a wonder that I wrote anything at all. We didn't spend too much time in the alpine that summer since we were trying to get as many forest plots as possible in the places we were working. Our Chichagof and Baranof based plant associations needed some adjustments for the northern mainland.

Thinking about goat use of alpine brought me back to the questions I had about control of flowering in our alpine species. What was especially interesting was that Vaccinium ovalifolium successfully bloomed and fruited, but growing right next to it, V. caespitosum didn't. In general photoperiod keeps plants from blooming in response to winter warm temperature events. Soil temperature seems to be the next trigger, probably because the plants enzymatic processes can function and they can access nutrients and water. One paper I found discussed a study on flowering of alpine plants on Hokkaido Island. They had plots at six elevations and keep track of flowering/fruiting over 3 years. A list of shrubs, V. vitis-idaea, V. ovalifolium alpinum, Harrimanella stelleriana and Phyllodoce aleutica only reproduced by fruit at the lower elevations, at higher they seemed to rely on vegetative growth. The author didn't find this shift in the graminoids and forbs, but did see an increase in semi-evergreen leaves at higher elevations.
Did find another paper about a study that transplanted a number of alpine plants to a greenhouse to determine the relative effect of photoperiod and temperature on flowering. About half were sensitive to photoperiod, some to both light and temperature and others reproduced by seed regardless of length of season (Saxifraga oppositifolia). I still don't really know what is going on with V. caesspitosum, except that there does seem to be a tendency for shrubs to abandon sex in less favorable conditions. I'm trying to think of how often I've seen fruit on that plant in any conditions. Definately not as often as in the forest species.

I haven't seen the petrels for several days, have seen harlequins and 3 white winged scoters on my path home.
Stopped by Moller park, Starrigavan and HPR on Friday with Eric, Kevin and Jamie. I was hoping to finally see a pipit, but no luck. We did see nothern flickers, hermit thrush, juncos, winter wrens, chickadees, scoters, harlequins (there seem to be a more this fall than I remember in the past).

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