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24, 35); font-family: helvetica, ari Interesting post and initially it does sound alarming. However, in checking -- and it's not clear in the original link either -- but the 87% dead, 13% alive seems to be the aggregate of what Fred observed on the road during each survey of 4-10 minutes length: it's not at all to be interpreted as an 87% kill rate, if that's the implication. Obviously, the dead ones would have stayed on the road to be observed where they died and could have accumulated over 24 hours (or more, if not scavenged) if Fred surveyed once a day, but probably most of the smaller numbers of live ones that he observed over a few minutes each time actually did manage to cross the road successfully (within a few minutes?), to be replaced by another batch that also crossed mostly successfully (in the next few minutes?). Without knowing the numbers of anurans attempting to cross per time interval, and the time period over which the kills accumulated, you can't estimate the kill rate, but it's not going to be up in the 87% range: putting in largely fanciful extra numbers, I came up with perhaps a 4% road kill. Perhaps Fred has a more solid estimate? One of the most remarkable statistics in Bev's link is that the road section Fred surveyed was 246 m long (1/4 km) and that this full length apparently was sampled each walk, resulting in an average of ~4 animals observed per meter. Over the 3 years surveyed, Fred therefore would have been making ~1000 observations total per walk, in a sampling time averaging about 7 minutes per walk. That's walking at ~2 km/h, by itself not unreasonable, but it means somehow recording numbers and identifying species at a rate of ~140 records per minute, or >2 per second. Even standing still I couldn't imagine how such a tally rate could possibly be achieved, so must be missing something. Steve (Hfx) ________________________________________ From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on behalf of bev wigney [bkwigney@gmail.com] Sent: Tuesday, April 5, 2016 11:28 AM To: naturens@chebucto.ns.ca Subject: [NatureNS] A shout-out for Road Ecology All, This morning, I wrote a post to my naturalist friends on Facebook concerning road ecology. Gale MacLean suggested that members of NatureNS might find this of interest too, so I’m reposting here. Read on: ---- I’m posting this link to a document written by friends, Fred Schueler<https://www.facebook.com/bckcdb> and Aleta Karstad<https://www.facebook.com/aleta.karstad>, as I think it may be of interest to some of you. It is entitled, "Reckoning Wasted Lives: Thirty Years of Road Ecology in North Grenville.” http://pinicola.ca/wasted_lives.pdf Now, before you think, "Well, where's North Grenville and what does it have to do with me?" - let me just say that it is what Fred and Aleta have been doing that should be of interest to you. For more than thirty years - actually, it's getting closer to forty years - they have been "doing the roads" in their area - studying what is happening on them, in what is now known as 'road ecology'. That involves keeping records of the movement of creatures that are crossing roads - both successfully, but very often unsuccessfully. To give you some idea of just what may be seen by surveying a small section of road, let me quote from the document (page 18):
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