South side - 1/8/20

January 8, 2020 (Wednesday) 10:15 am – 12:15 pm: 134 dead newts
It was dry and cold during the survey. It has been dry for a few days. The road was mostly dry. I documented 0 live and 134 dead newts, only one of them was fresh. Most of the newts seemed to be adults.
I only saw one other amphibian on the road, not sure what it was.
Coverage: south part - from the stop sign till the intersection.
Rainfall: (MTD: 0.01 in; YTD: 12.36 in) cold, dry
Traffic: 1 truck, 15 cars (including 1 maintenance pickup - midpen), 4 bike, 0 pedestrians.
I will update the numbers later after uploading the observations.

Posted on January 9, 2020 05:45 AM by merav merav

Comments

Thanks for patrolling the south side, Merav. It's been at least a couple of weeks since a south patrol was done.

Posted by truthseqr about 4 years ago

now that I'm back, I hope I'll be able to do more. I've got some family visiting, beginning next week, but I think I should be able to squeeze it in once a week as usual. (I hope they won't ask to join me...)

Posted by merav about 4 years ago

Here's a map of your newts for this day. I've been looking at this for my observations and thought the patterns were interesting, so I thought I'd check out other people's as well.

Posted by sea-kangaroo about 4 years ago

Thanks! It was interesting doing the south road, but I think I still prefer the north :)

Posted by merav about 4 years ago

I agree that the north half is more interesting. Or possibly it's because there's more roadkill in the north. As long as you're out there, might as well record as many as you can for the time you spend.

What's interesting to me about the above map is the gaps where no dead newts were found. I wonder about those, especially around Soda Springs Canyon.

Posted by truthseqr about 4 years ago

Something I've been idly considering-- there are a few places along the road where there are underpasses (drain pipes) of various sizes already in place. If those correspond to blank/lower-mortality spots, maybe the newts are using them for safe passage. I'll geolocate them next time I'm out and see if there's an obvious correlation.

Or maybe just a natural feature of the terrain-- too steep, or just there's a drainage nearby that the newts prefer to travel along.

Posted by sea-kangaroo about 4 years ago

I hadn't thought of that, @sea-kangaroo. Good thinking! I'll be very interested to hear what you find.

There's a place just south of the rowing club where there's a stream that passes through a culvert to dump into the reservoir. I've seen many dead newts there and I've wondered why the heck aren't they using the culvert?? A local resident said she sees newts on the road eating earthworms, and suggested that may be why they're on the road.

I've read that under-road culverts are sometimes not effective because they're too dark and the newts can't see through to the other side. Or that the metal feels unnatural and needs dirt or sand at the bittom. Some conservationists use herp netting to "herd" the newts into the culverts. Some have designed culverts with lights & cameras inside. It's a problem that hasn't been completely resolved.

Posted by truthseqr about 4 years ago

Good points! Some of the culverts also can have some pretty high-velocity flow in them, so I'd imagine the newts might be a little reluctant to go whitewater rafting/over a waterfall.

I'll take some notes about the size etc. of the drainpipes as well.

Posted by sea-kangaroo about 4 years ago

Ha! That's a fun visual - newts rafting through high-velocity whitewater and over waterfalls. LOL

Posted by truthseqr about 4 years ago

also keep in mind they need to go back from the lake to the hill. most of the culverts end up in the air, making that impossible

Posted by merav about 4 years ago

Yes, that's the sad thing about all those culverts. If they help, it's only in one direction. Some have as much as a 10 ft. drop. Only the two big cement culverts at the two canyons would be bidirectional. Someone talked about building shelves above the water line to help the newts traverse the tunnels. Also someone suggested replacing the other smaller culverts with new ones that the newts could use on the return trip. But I imagine that would be really expensive. Maybe that option could be used when building new roads in newt habitat, though.

It seems the current favorite option being considered by the mitigation team is elevated road platforms with tunnels for the newts to pass through and holes to admit light. USGS naturalists used that option in the Sierras with much success. Cost is about $350K. Downside is that it can only be used on straight roads, which leaves out both of our high-mortality canyons.

Posted by truthseqr about 4 years ago

@sea-kangaroo, I think there's a govt document out there somewhere on the web that marks the location of all the culverts. I think I googled "Alma Bridge Road" to find it.

Posted by truthseqr about 4 years ago

Are the "elevated road platforms" like hollow speed bumps? Or like a bridge thing? (I'm not having google luck finding out)

Posted by sea-kangaroo about 4 years ago

Here's an excerpt from an email I received from Cheryl Brehme of the USGS, who helped implement the ERS mitigation in the Sierras and is a member of the mitigation team for Lexington:

"We agree that improving the culverts and putting barriers in the immediate vicinity of the culverts would certainly be a beneficial part of any mitigation strategy for the newts. Regarding elevated road segments (ERS), we are also working on engineering designs for permanent ERS structures for primary roadways but it will likely be a year before they are completed. So this would be a preliminary study to inform the efficacy of a more permanent structure(s) which could be any length- providing large areas for newts to move across the road in combination with improving potential passage through the culverts. It seems like a perfect place to try this mitigation strategy and as Fraser noted, there are many folks interested in finding a good location to further test this ERS concept that has the potential to greatly increase connectivity across roads for migrating amphibians in these types of situations. One thing to consider with long lengths of barrier fencing is that not all animals make it to the underpasses, so it is possible that connectivity can be decreased after addition of tunnels and barrier walls. A recent publication by Ottburg and van der Grift showed that Bufo bufo travelled an average distance of 50m along a fence before "giving up" and turning around back into the upland habitat. They observed a large decline in the population over 5 years after the tunnels and barriers were installed to address high rates of mortality on the road in between their breeding ponds and terrestrial habitat. Similarly, we just presented a poster at ICOET from our studies at Stanford showing the average give up distance is about 60m for California tiger salamanders. Water and sediment flow at the site must also be considered when placing long sections of barrier fencing and/or more tunnels. "

Posted by truthseqr about 4 years ago

This is a great article by Cheryl Brehme (ecologist with USGS) that also shows pictures of what the elevated road segments look like.
https://www.usgs.gov/center-news/toad-crossing-ahead-new-study-tests-elevated-roads-underpasses-rare-toad?qt-news_science_products=1#qt-news_science_products

Posted by truthseqr about 4 years ago

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