Friday 21 March 2014

Weekly posts

For a while now I have been thinking about trying to post more regularly. There are two reasons for this; first, the blog gets pretty stagnant at times and I think it would be better if we had more regular material, and second most of my week is taken up staring at my computer and I thought this would be a good way to break up my week and get feedback on things I am thinking about or working on currently. These posts are likely to be more on the science side, but hopefully I will be able to do enough fishing and hunting to keep it somewhat interesting.

This week all I have are links to other sites that I thought were interesting:

Lately I have been trying to learn more about the science-policy interface with the idea of eventually trying to better focus my own work towards policy. Here is an interesting perspective recently published in Nature (link). The author links to a code of conduct for scientists developed by the Science Council of Japan (link). Interesting that Japan has a specific set of guidelines for science communication and the role of scientists in society. Not sure the US or Canada has anything closely resembling this.

I recently read this paper in Conservation Biology that retrospectively assesses the IUCN status of most carnivores and ungulates in the world (link). Most have had a decline in their status over time. Interesting thing to think about from this is that our perspective on a species status tends to be more near term. The authors suggests this can lead to shifting baselines in our expectation for the conservation of species- e.g. if a local population has stabilized over the last decade, but exists in only 10% of the range it occupied 30 years ago, is this really a success?

Lastly, a super nerdy link about data compression (link) and R. R's basic data compression outperforms the compression of other formats even after they have been zipped.




Sunday 16 March 2014

Winter beasts

I went bison hunting last weekend. Nathan, who you'll remember from my 2012 sheep post, came as well.

Bison hunting is a winter activity, with the season running November to March, with a six-week hiatus from New Years to mid-February. It's also a mechanized activity; bison live well back from the road, and even if you could manage to ski or snowshoe into where they are, there's no way you'd ever move it home. Snowmachines and skimmers are the order of the day.

What to pack when hunting 1000kg animals at -25C


Our plan was to head into the backcountry north of Kloo Lake early Saturday morning, overnight in the hills, and hit the highway again by dusk on Sunday. It was new country for both of us, but we were armed with information from a few people who had hunted there before, and I'd gone over the best aerial imagery I could get my hands on, and figured out some trails that would get us into where we wanted to go. We also had these to go on.

A quick digression on Yukon bison. The wood bison currently in Yukon are descended from animals introduced by the government in the 1980s and 90s, mostly from Elk Island stock. There's historical evidence for wood bison presence in Yukon, but it's been hundreds of years since the last ones disappeared. There were a few reasons for introducing wood bison, with a major one being the establishment of one of several independent, self-sustaining herds as part of a Canada-wide conservation strategy. The herd's done well. Tags went from draw to over-the-counter tags a few years ago, but even so bison numbers are still growing. As the population's beyond its target, hunters are encouraged to take bison (particularly cows) to keep it in check. They're not easy to hunt, though - they're highly mobile and increasingly wary - hence the government-issued bison maps.

Back to the hunt; Saturday dawn, and we're at the trailhead. We headed out, with the goal of getting north of Kloo Lake, and looking for sign.

Three ways to turn gas into meat?


Another digression, on process. Bison move, and aren't the kind of animal to be dependably found in one location for much longer than it takes to feed, digest and wander off. The two ways of encountering them are to glass from a vantage point, trying to spot brown lumps on white snow, or to ride through likely-looking country and try to cut tracks, which if they're fresh enough you follow on foot/snowshoes. Likely-looking country, in the case of bison, is usually associated with grazing - they feed on south-facing grassy hillsides, and in lowland sedge meadows. Cows and calves usually move in small groups, whereas lone animals seem to be bulls (in my experience, anyway). Speaking of experience, bison have rapidly gained a bunch when it comes to hunters, having been hunted for a few years now. Nothing moves them out like the sound of a snowmachine; approaching on foot seems the only way to get close. /digression

Our first foray off the lake, not knowing exactly which route we were after, followed a narrow, oxbowed river, incised well below the forest level, north off the lake. It was fun riding - like being on a particularly winding rally course - until Nathan did this:

Gun it and hope.

My gut reaction, as he broke through the river ice, was to figure we were headed for home once we'd fished the sled and gear out the river. Impressively, though, Nathan pulled off a successful emergency water-skim (which essentially involves pinning it and floating on the cushion of air/water/slush the track's pushing down into the water), and reached the other side without getting much more than his track wet. After finding a safe(r) spot to cross back, we changed our minds on this route, and found another.

We traveled a lot the first day, making it about 45km in. There was lots of old bison sign, and we actually saw some very distant bison (one group of ten cows and calves, and a lone bull) on inaccessible slopes, but nothing we could possibly get to. Ask dusk fell, we set up camp in a spruce thicket. It is possible to make an excellent bonfire if you have a chainsaw and unlimited firewood at your disposal.

Camp, at a rare lull in bonfire activity.

Waking in a tent gently snowing our frozen breath back down onto us, we got up, had a leisurely fireside breakfast, broke camp, and headed to higher ground to try glassing (given our inability to find fresh sign the day before). Greater altitude brought some useful vistas, but no accessible beasts.

Looking south toward Kloo Lake and the St. Elias Range.

More riding, through promising-looking but empty country. It's been an odd winter, with very little snow since a warm spell in January melted December's big dump. Without a heavy snow layer, the meadows in higher country are accessible, and the pattern that started making sense to us was that most bison were up high, away from hunters.

As the day wound down, we cut a track of a lone bull in a sedge meadow. The tracks were reasonably fresh - perhaps from that morning - and we packed up and left the snowmachines behind, following the tracks.

Bull tracks.

While the tracks showed methodical grazing in the meadow where we first encountered them, once they left the meadow, they showed the bison making a relentless bee-line for the distant hills. We followed slowly and carefully at first, tuned up to the possibility of coming across the bison any minute now. As we tracked further (and it got later in the day), we realized a faster pace was the best option; pretty soon we were sweating rapidly uphill, trying to gain ground on an increasingly determined-looking set of tracks.


Initial excitement.

By 6:00, we had to call it; we'd tracked the bull for 5km, through enough rough country that, had we encountered it right away, would already have meant taking an extra day to cut a snowmachine trail into. Given their size, and the work required to get them from dead lump in the wilderness to brown paper packages in the freezer, there's always a bit of relief in not getting a bison. We decided to savour that, and headed back for home.

The hills that contain at least one bison.