Monday, 31 May 2010


Link is here.


Friday, 28 May 2010

Prodigious Pronghorn Population Projections

ResearchBlogging.orgCan the presence of wolves be good for prey species? Intuition seems to suggest the answer is no. After all, wolves eat prey, and being eaten is fairly bad for one's health. Wolves are implicated in a number of natural declines of prey species in a number of systems, especially in closed populations where immigration can't bolster floundering populations. The use of wolf control is a controversial tool which I won't discuss at great length here, but one of the key assumptions is that it increases survival of some age classes of prey.  Before I go much further, I've added some entries to my glossary over to the right, for ecological terms.

One of the most vulnerable age classes are neonatal animals and juveniles, or the year's young. While surviving to second or third year doesn't guarantee you'll survive to old age, if you're a deer, it does mean you're fairly less likely to die. Adults are very good at surviving, since evolution has shaped them to be surviving machines, capable of hyper-vigilance, amazing running speeds, and so on. The young, however, enjoy much less of that sort of protection. There tends to be lower survival for the young of the year, and this can be a major factor governing population fate - if you die young, it's hard to do much breeding.

Re-colonizing wolves provide a wonderful mini-experiment to see what the effects of their presence or absence is on various age groups. Kim Berger and Mary Conner, both at Utah State University at the time, studied the effects of re-colonization on pronghorn neonatal survival. Berger and Conner selected two study sites with wolves, and one that was free of wolves in Wyoming. Coyotes were much less abundant at the sites with wolves than they were at the sites with wolves, as they had demonstrated in a previous study.

Fawns were located through a good old fashion leg-work (they must have good vehicle access out there!), and through watching gravid females until they dropped their fawns. They would capture the neonates, weigh them, age them, record the sex, and assess over-all health in a few categories before fitting them with a breakaway radio collar with a mortality sensor. When the animal dies, the radio signal from the collar changes, allowing the researches to swoop in and look for cause of death. Some things they would look for include
  1. whether the fawn was alive at the time of the attack
  2. tracks, scat, hair, and any caches that might help them identify the predator
  3. signs of starvation or other accidents.
The sort of predator who killed it could be classified based off of previously described characteristics. One thing I've always wondered is if there is a better way to ID the cause of death more adequately. However, kill site characteristics have been frequently used before, and will suffice for here.

Ignoring the factors of survival for a moment, there was much greater fawn mortality among wolf free sites than wolf abundant, with as low as 0% survival in one year. The overwhelming majority of the mortality came from either demonstrable coyote predation, or likely coyote predation in those wolf free sites. Coyote predation was still a major factor in wolf abundant sites, but over-all survival was much higher in all years, with the lowest being 24%, higher than the highest survival in any year in the wolf free site. Thus, the presence of wolves appears to beneficially change the survival rate of pronghorn calves through reducing coyote mortality.  Modelling this forward using other vital rates for pronghorn, they find that the wolf-free sites will gradually suffer total collapse, while the wolf abundant sites are quite stable. Clearly, our earlier intuition was not entirely correct about the effects of having wolves in these populations.

This fits nicely into a framework that I've previously mentioned, which is the "Meso-predator release hypothesis." The idea is that wolves or other apex predators (bears, cougars, etc.) keep middling scavenger-predators (such as fox, coyote, racoon, skunk) suppressed when they're around and healthy. They can suppress them through feeding on common prey, attacking meso-predators directly, and so on. This is a top-down effect, where high trophic levels (animals that do bulk of the eating other things) influence the composition of the lower trophic levels (prey; the things that are eaten).

Within the state of Alaska, it begs the question whether there are significant numbers of meso-predators, and whether they are similarly released in times of intensive management. A entirely separate and important question is whether this release negatively impacts prey populations. To my knowledge, no one has done any sort of extensive study of meso-predators in the state. Our knowledge of background fox and coyote density is not very good, and after asking several people, I begin to suspect there are no density estimates for regions of the state. Given that, I am sure no one has looked at meso-predator densities during periods of IM. Anyone who knows otherwise is encouraged to email me! However, the latter most question is probably best identified - there have been studies of calf mortality after bouts of IM, and I don't anyone's identified a shift in mortality towards meso-predation.

Berger KM, & Conner MM (2008). Recolonizing wolves and mesopredator suppression of coyotes: impacts on pronghorn population dynamics. Ecological applications : a publication of the Ecological Society of America, 18 (3), 599-612 PMID: 18488620

Wednesday, 26 May 2010

Scientists are getting old

Here's an interesting piece (sorry for the paywall) that argues what I've suspected - Science is getting older. And that's not a good thing.

Recently, I was telling a student considering making the jump into Math and Astronomy (from English) that they shouldn't worry about how old they are, as the average graduate student is now around 30 something. I forgot where I read that, but now I wish I could find it again. This mean most people start their professorial career (in academia) or move to commercial labs in their late 30s, if not 40s. The man who heads my research group at my last job typified this, having gone back to college when he was in his late 30s. Granted, a large chunk of his 20s was taken up by being in Vietnam.

Just to be contrarian (a healthy thing, in science) I'm not sure what the world needs is more collaborative research. Sure, it'll let us tackle bigger and bigger questions, but those big questions are increasingly narrow. Further, it feels like these massive collaborations are sort of the cludge solution to many of the problems. Instead of clever experimental design, we're substituting brute force.

Sometimes, I think the solution is to make people in both academia and industry to take a mandatory Patent Office period.


Friday, 21 May 2010

Unimak and South West caribou instability

I was fairly surprised to see that there was a story about the Unimak Caribou Herd (UCH) in the Alaska Daily News this morning; I checked around and found the source of this new burst of public awareness, which was a press release posted on ADF&G's website. As someone who knows a few things about the South West and Alaska Peninsula herds in general, and about the situation specifically, I thought I might try to add meaningfully to the conversation.

To the right I have a figure of the area we're talking about. I'm using ADF&G's figure from their website, since it's far better than my own. In the region, there are 5 designated caribou herds, plus feral reindeer on Kodiak island (which is a hotbed of introduced species). Mulchatna (MCH) is a conglomeration of multiple herds, including the now defunct Killbuk, and a few others, which merged into the mass we have today. Nushagak is actually quite separate from MCH because it a) has separate calving grounds and b) is entirely man-made, made from transplanted Northern Alaska Peninsula Caribou (NAP) a couple decades ago.

The NAP has quite a bit of range overlap with MCH, and recent authors have used this to describe the situation down there as a "Meta-population," that is to say a population of populations, with patches of terrain gaining and losing caribou at some background rate. I'm not sure I agree with their assessment, for technical reasons. However, NAP and the Southern Alaska Peninsula Caribou (SAP) don't really mix, as SAP and NAP are constrained short of Henderson Bay (generally). Similarly, UCH and SAP don't really mix, because of the False Pass that the village is named for.

Unimak caribou probably descended from animals which somehow made it across False Pass, and settled on the island. The island itself is lightly inhabited, and has broad plains with a few major volcanos sticking out (It's the AP, volcanos are like seagulls. ;) ). The Alaska Peninsula and Unimak island are both fairly marginal caribou habitat, or at least appear to be as over the long term, caribou have a hard time finding any equilibrium census, and they tend to fluctuate wildly over time. It's tempting to blame this on poor lichen, human harvest, other predation, and severe weather events, but to be completely honest, any satisfactory explanation of population dynamics out there probably must include all those factors.

So that's to say the area isn't a stranger to precipitous caribou declines. In the late 40's, NAP is thought to have scrapped along at a mere 2,000 animals, before peaking again at 20,000 in 1984. However, even this 10 fold didn't come as low as SAP, which declined to 600 animals as recently as 2007. After intensive management, the calf survival rate was brought up significantly in 08-09, and the population appeared to inch its way up so slightly to a slightly higher census.

In UCH, the population is at a mere 400. Harvest has generally been 10 animals (more or less) for the past decade, with no harvest being allowed in 09-10 regulatory year. In general, the level of human harvest represented a negligible portion of the herd until the decline between 06 and 09 censuses. Hunting on the whole AP has been "Verboten" for the last regulatory year.

The UCH's problem is illustrated through two things. First, it's abnormally low Calves per 100 Cows ration. It's 3:100. Needless to say, that is abnormally low. SAP had a lower ratio until intensive management was instituted, so it's not to say it's unrecoverable. However, the second illustrative problem is the extreme sex ratio fluctuation that's occurred. Currently, there are 5 bulls for every 100 cows in UCH. While Caribou are harem breeders (One male breeds with many females), this ratio is probably contributing to the other, abysmally low Calf-Cow ratio. There  just isn't enough bulls to "Cover" all of the cows.

So, I hope I've convinced you that it's not hyperbole when one of my good friends in the agency said "We have concerns that in one to two years, the herd will be on a trajectory that will cause it to cease to exist." While I'd put this possibility on the low end of things (Maybe 5-10% chance), I have to agree with his assessment on the whole. Discussion up to this point has focused on rescue transplants of males. Hopefully, the thought goes, additional males could cover the females not currently getting covered. The long-term genetic consequences of this is worrisome, but the short-term demographic consequences of the extreme sex ratio is far greater, and we can mitigate the genetic effects through appropriate management.

This development relates to the other factor of the cow:calf ratio, which is survival-to-census. Wolves can be highly effective predators of caribou calves, as can bears (for a short period). The argument goes that wolves are at a "Population High," and therefore intensive management is warranted in order to preserve both caribou and wolves long term viability on Unimak island. Most people will generally agree that IM was somewhat effective in bringing SAP on an upward trajectory, and we'll see how effective it was long-term when those 2008 animals really get to breeding in 2010.

However, long-term, I think we need an over-all strategy. South-Western caribou will go through population fluctuations much greater percent-wise than other herds in the arctic. This is inevitable, unless climate change has the unforeseen boon of stabilizing caribou cycling. We have three long-term directions we could take. First, we could intervene and attempt to stabilize the system through clever pushing-of-the-buttons. This, I'm sure, will be expensive. Second, we could supplement Caribou to stabilize them, turning the AP into something akin to the National Elk Refuge. This would be potentially less expensive, but have some major eco-systems wide effects. Or, we could manage for natural ecosystems, which is a fancy way of saying "Take our hands off the wheel and let the truck go wherever." All three have their strengths and weaknesses as options. All three require value judgements. However, a consistent direction is far preferred to a reactionary approach.

Slides from the FWS presentation from ADF&G, and the table is from the 09 caribou inventory report.

Thursday, 20 May 2010

From the Wasted Money department

Austria has the same problems that every other country has - some roads are dangerous, and there are too many motor accidents on them. Most of the time, people send in civil engineers to think how they can rout traffic to minimize accidents, or change the roads to make accidents less likely (or more survivable). When I first moved into Fairbanks, I moved to the corner of Geist and University, one of the most accident prone intersections in the state, so I'm well familiar with the concept.

Well Austria isn't bound by such conventional thinking. Why send in civil engineers, they thought, when they could send in a team of crack druids to fix the problem. (Yes, Druids).

Good call on that. You wouldn't want anyone making fun of you for sending in Druids to move energy about, instead of taking a more practical approach. That would just be intolerable.

I especially love this bit:
But the druids warn that they could be fighting a losing battle as the biggest cause of radiation disruption is mobile phone masts.

I wonder if they ever met this guy.


Tuesday, 18 May 2010

Beer Notes from Sunday

Coper Hook Copper Ale, by Redhook Ale Brewery, Washington

First: despite it's name, it's an amber ale. That said...

In Red Hook's typical overmoulded bottle, frail and translucent as any of their other line, Copper Hook has no great external appeal. The beer is presumably copper colour - orange, more like - with light-mild carbonation foam. It smells of fruit - heavy citrus - with a hint of something peppery. It feels smooth across the tongue, with no real carbonated bite. It has the aforementioned citrus zest, but it's less conveyed by taste than it had through aroma. The hops aren't as heavy-handed as in some of their other offerings. There's a light, creamy aftertaste, followed by a clean, dry feeling. There's nothing overwhelming about this beer, but instead a nice, surprising combination of flavours that play well together. 3.6 of 5. B.

Monday, 17 May 2010

Think it's dry now?

I tried to post this a few weeks ago, but Blogger wouldn't let me. So I'm going to give it another try.
It seems the very low snow condtions, coupled with the warm weather predicted for the year, the CPC is forecasting a hydrological drought in much of Interior Alaska. I can attest to the fact that the upper Chena is very low, since even my kayak had problems with the shallow water last weekend.

Friday, 14 May 2010

From one mad-man to another




The Death of Fr. Juvenaly

A friend of mine send a link to me. I don't know why he did, but I'm very glad he did because it has a very good account of 1790s history in it. It's about the death of one of Alaska's earliest missionaries, Fr. Juvenaly. Fr. Juvenaly was a Russian orthodox, and moderately old for point in history - remember than amongst Whites in America, half of America was under the age of 16 in 1790. He was, therefore, a bit old to be "gallivanting around" as a missionary. None the less, he apparently came first to the Kenai, then to Kodiak, where he crossed to the Alaska Peninsula/Iliamna area, never to be seen or heard from again. What fate had he met? Was it the Iliamna monster?
[...] Then, about a hundred years later, an American historian, Hubert Bancroft, published an account of Father Juvenaly’s death purportedly based on the priest’s own words as he recorded them in a diary that a man named Ivan Petrov claimed to have found and translated. According to this diary, Father Juvenaly fell into temptation, having been seduced by the daughter of a local Indian chief, and then was hacked to death for refusing to marry her. That is all I knew about this incident until my Yup’ik father-in-law, Adam Andrew, who was born about 1914 in the mountains near the source of the Kwethluk River, decided to tell me the story about “the first priest to come into our region.”
The whole story is wonderful. You can continue reading here.

Thursday, 13 May 2010

Beer Notes from Sunday


Mud Slinger Spring Ale, by Redhook Ale Brewery, Washington

Tuesday, 11 May 2010

North From Anchorage

Here's a video from somewhere between 1925 and 1930 that I found online at the Alaskafilmarchives account at youtube.

I really like this account, and think it's a good idea - this opens it up to anyone, not just people in Fairbanks or Anchorage. My one regret is that the films are mostly of white towns and not much otherwise. Still, even though it's poorly representative, it's a good source. It's always interesting to see what it was like before we were alive to see it.

Monday, 10 May 2010

Random things

It's true. I basically follow any instructions I get blindly. Well, I don't keep my photos organized in such a way to make it easy for me to go to the eight folder, but in keeping with the spirit of things, I opened 2008, went to the 8th roll, and opened the eighth picture. And it was my most fearsome nemesis: TIREEATER
Tire-eater ate tires. She wasn't very big, but she had a huge apatite for rubber. Or, more accurately, the salt on my tires. You see, I'm told that when alders and willows get stressed, they put out secondary compounds to poison the Snow Shoe Hares. However, the hares have evolved the ability to detoxify the compounds. However, the process requires huge amounts of salt - I'm not sure if they need Sodium, Chloride, Potassium, or what. Tire-Eater got her salt from chewing on my tires. Tires are $($(*$ing expensive. But what could I do? I couldn't shoot her - not that I didn't want to, but I would shoot my truck in the process! She wouldn't come in the same direction twice, and so snaring her wasn't an option. And it wasn't winter, so I couldn't trick her into using a snared path.

It turns out the solution was to attract some foxes to my area. >:)

Problem solved!

Beer Notes from Saturday, and a bonus movie review!

Red Hook ESB, by Redhook Ale Brewery, Washington
The bottle is fairly transparent, and you can see how clear the beer is without even the courtesy of a pour. Continuing in the trend of moulded glass, the bottle shows wheat in relief, along with what I have to assume are mountains from their logo. The beer is the colour of clear honey, with a light beige head that stretches tall after even the lightest agitation. The beer smells strongly of hops, and little else. Sipping it, this beer personifies the trend towards a strong hops flavour, with a background of grains. It's very dry in the mouth, and the bitter qualities seem to leave the palate more bereft of moisture after drinking than it had before. The beer is a little too simple, and a little too one directional. While it would be easy to learn to appreciate this beer, I'd prefer to avoid having to do so. 3.05 out of 5. C+

Ironman 2 - Enjoyable. Worth the 7 dollars. Not as good as the first, but the 1st set a high bar. Do NOT bring your screaming 2-year old, though. Comicbook Nerds should stay until after the Credits.

Friday, 7 May 2010

Second thoughts

I like oil. It makes my snowmachine run, which lets me have fun, get food, and go trap. This is very important to me, and running a dog team is not an option for me. This picture makes me re-think offshore oil in the Arctic, though:
As bad as this disaster is, I can't imagine floating chunks of ice would make it any less worse. I love our home too much to want this to happen to us.
There, I've got the politics out of me for the month.

Thursday, 6 May 2010

Bevers! In! Spaaaaaaace!



Tuesday, 4 May 2010

Abstracts: Effects of a Snowshoe Hare decline on Survival of Dall's Sheep in Alaska

I can't believe I didn't post this. Steve Arthur is a good biologist, and a good person, and the study is wonderfully clever. In his talk he dissected the relation between hare abundance and predation on Dall's sheep lambs. Coyotes increase in abundance after hare highs, and when hares subsequently plummet, predation shifts to the lambs. But that didn't become apparent until the data was analyzed as a function of survival, and not census, as abundance was generally positively correlated with hare abundance.

Very clever.

Arthur, Stephen M., and Laura R. Prugh

We estimated survival of Dall's sheep (Ovis dalli) in the central Alaska Range during years of differing snowshoe hare (Lepus americanus) abundance to test whether indirect interactions with a cyclic hare population affect Dall's sheep either negatively, by subsidizing predators (apparent competition), or positively, by diverting predation (apparent commensalism). Annual survival of adult ewes was consistently high ( = 0.85); whereas, lamb survival was low and ranged from 0.15-0.63. The main predators of lambs were coyotes (Canis latrans) and golden eagles (Aquila chrysaetos), which rely on hares as their primary food and prey on lambs secondarily. Coyotes and eagles killed 78% of 65 radiocollared lambs for which cause of death was known. Lamb survival was negatively related to hare abundance during the previous year, and lamb survival rates more than doubled when hare abundance declined, supporting the hypothesis of predator-mediated apparent competition between hares and sheep. However, stage-specific predation and delays in predator responses to changes in hare numbers led to a positive relationship between abundance indices of adult Dall's sheep and hares. Lacking reliable estimates of survival, a manager might erroneously conclude that the relationship was apparent commensalism. Thus, support for different indirect effects can be obtained from differing types of data, demonstrating the need to determine the mechanisms that create indirect interactions. Long-term survey data suggest that predation by coyotes is limiting this sheep population below levels typical when coyotes were rare or absent. Understanding the nature of indirect interactions is necessary to effectively manage complex predator-prey communities.

2d/3d illusion

Here's a neat illusion, sadly done as a you-tube video.

Tip of the 3d illusion to Bad Astronomy.

Monday, 3 May 2010

Beer Notes from a few days ago

Grimbergen Blond, by N.V. Br Alekn-Maes, Jumet Belgium. 

The artwork is a bit gaudy on this 11.2 fl beer - some sort of hereldic eagle - but not too over the top. The beer pours a thick head, the beer itself a clear straw yellow. The predominant smell is yeast, but with a backing of fruity esters. The  first thing you notice is the clouded, muzzy mouthfeel of the beer, thick and silty. It has faint taste of bananas, backed with a carbonated bite. There's a light citrus zip, but the overwhelming silt feeling still dominants. It's hard to drink anymore than a little of this at a time, before it feels like your teeth are being sandblasted - bring plenty of water. 3.1/5 C+