Update, Saturday 25 July 09:
I took the Radar-mobile (aka: TMR - 'toyota, mobile radar') out for a spin last night, and took some screen images at Capitol Lake to compare with those from 2 years ago. Dramatically fewer bats over the water, and almost none over the mudflats. Not a surprise. Previous times the Radar unit showed that they were all over the lake's 3 chambers, the fewest were over the river channel (faster water, fewer insects?). That is the only place water has remained during this draining event. So even the little remaining water may be of little value to these bat moms struggling to feed themselves and their pups back at the nursery colonies, who are by now getting to be teenager size (and yes they are still nursing them!).
Saturday, July 25, 2009
Friday, July 24, 2009
Karen Fraser kindy sent me an email this morning, reporting the she spoke with the G.A. director Linda Bremer (G.A. manages Capitol Lake) about refilling the lake. Senator Fraser reported that Bremer said that as of 6 p.m. yesterday (Thursday) that they had closed the dam, so the refilling of the lake could proceed, 'to help the bats.' Thank you very much to both Linda and Karen.
While this will start getting fresh water back into the basin, nobody knows how long it will take for the 200+ acres of exposed mud to recover its 'macroinvertebrate' community (the bat food, midges, arising from the mud) , or the native plant communities, and therefore the food chain that has been damaged by this event. Stay tuned to the Sunday Olympian, I think that John Dodge may have talked to others who know (way) more about this for his Sunday column.
While this will start getting fresh water back into the basin, nobody knows how long it will take for the 200+ acres of exposed mud to recover its 'macroinvertebrate' community (the bat food, midges, arising from the mud) , or the native plant communities, and therefore the food chain that has been damaged by this event. Stay tuned to the Sunday Olympian, I think that John Dodge may have talked to others who know (way) more about this for his Sunday column.
What were they thinking?
The dedicated counters had 1,200 bats exiting the pier at the Woodard Bay bat colony last night, there were 3,300 last Thursday. The counters are going out to count again tomorrow night, as there was a SW breeze tonight. That can throw off the count--the bats seem to head into the wind more, which could have put some of the exiting bats out over the water, out of sight of the counting. We've used an extra person with a scope to verify this on occasion. With that caveat, plus that this is the time of the summer with the highest variability in the counts, I can report that we've never had a one-week change of this magnitude (-2,100).
Is this an effect from draining Capitol Lake at the most critical feeding period of the summer maternity cycle? We can't say for sure, but it certainly could be. The vast majority of the pregnant and nursing bats from several large maternity groups travel many miles to each night to Capitol Lake, feeding on minute aquatic insects like midges, mayflies, and the like. These insects spend most of their life aslarvae in the muddy bottom of the lake. Then one fine night they mature, pop to the surface, shed their extra layers, flap their new wings, and rise from the water's surface... into a bat's mouth! They don't do this from a dry mudflat like we have now. So, the normally super-rich lake is now effectively a desert, as far as these thousands of nursing mother bats are concerned. No, they won't have this food source if/when the area is converted to intertidal mudflat.
What are they thinking?
How did 260 acres of fresh water habitat... in downtown Olympia... below the Capitol Campus... whose fate has been under public discussion for the past 6 years... jsut get drained without consultation with anyone who monitors the flora and fauna of the lake?
Consider the readers' comments from the July 16 Olympian article about the draw-down, which at that time was reported to be a few feet lower for a short period of time:
http://www.theolympian.com/southsound/story/911862.html
It was reported in the July 16 Olympian article that " Lakefair officials learned a couple of weeks ago that the lake would be drawn down during Lakefair." Since this was planned at least two weeks in advance, it hardly sounds like an emergency. Doesn't this mean that G.A. approved this proposal in June?
Update, Saturday 25 July 09:
I took the Radar-mobile out for a spin last night, and took some screen images at Capitol Lake to compare with those from 2 years ago. Dramatically fewer bats over the water, and almost none over the mudflats. No, not a surprise. A couple years ago at this time they were all over the lake's 3 chambers, the fewest were where the river channel is (faster water, fewer insects). That is the only place water has been during this draining event. So even the water that was there was the last place the bats would normally feed (as in poorest foraging locations).
Is this an effect from draining Capitol Lake at the most critical feeding period of the summer maternity cycle? We can't say for sure, but it certainly could be. The vast majority of the pregnant and nursing bats from several large maternity groups travel many miles to each night to Capitol Lake, feeding on minute aquatic insects like midges, mayflies, and the like. These insects spend most of their life aslarvae in the muddy bottom of the lake. Then one fine night they mature, pop to the surface, shed their extra layers, flap their new wings, and rise from the water's surface... into a bat's mouth! They don't do this from a dry mudflat like we have now. So, the normally super-rich lake is now effectively a desert, as far as these thousands of nursing mother bats are concerned. No, they won't have this food source if/when the area is converted to intertidal mudflat.
What are they thinking?
How did 260 acres of fresh water habitat... in downtown Olympia... below the Capitol Campus... whose fate has been under public discussion for the past 6 years... jsut get drained without consultation with anyone who monitors the flora and fauna of the lake?
Consider the readers' comments from the July 16 Olympian article about the draw-down, which at that time was reported to be a few feet lower for a short period of time:
It was reported in the July 16 Olympian article that "
I took the Radar-mobile out for a spin last night, and took some screen images at Capitol Lake to compare with those from 2 years ago. Dramatically fewer bats over the water, and almost none over the mudflats. No, not a surprise. A couple years ago at this time they were all over the lake's 3 chambers, the fewest were where the river channel is (faster water, fewer insects). That is the only place water has been during this draining event. So even the water that was there was the last place the bats would normally feed (as in poorest foraging locations).
Today (Thursday, July 23) I sent this to a bunch of folks who maybe should have known about the lake draining before this happened--but apparently didn't:
From: Greg Falxa
Sent: Thu 23-Jul-09 16:16
To: svaland@ga.wa.gov; fraser.karen@leg.wa.gov; jhyer@ci.olympia.wa.us...
Subject: Capitol Lake draw-down's impact to regional bats
Did anyone involved in this decision ask the question "what impact will this have on the region's bats?" I am asking this as a serious question.
After reading the G.A. press release I expected possible dismay, but was shocked to see how little open water remained in Capitol Lake when I went to check out this draw down. I cannot think of a worse time for this to occur; this part of July is the most critical of the energy-demanding time for the many thousands of nursing mother bats which congregate nightly to feed at Capitol Lake. They spend the night feeding here, then head back to their colonies to feed the young. Right now, the young are nearly adult-sized yet still dependent on their mothers' milk. That means they are needing the most resources of any time they are nursing. By this week, a few young might be making their first trips to the lake as well, when they are just learning to forage for insects emerging from the surface of the open water.
Last Thursday at dusk, 3,300 bats exited the Woodard Bay nursery colony; most head directly to Capitol Lake to feed. This is only one of three large groups of bats--that we know of--that use the lake as a primary feeding area during this 'maternity time.' This is not new information; it has been presented by various people many times during the formal and informal discussions about the fate of the Capitol Lake: to CLAMP, to GA, to WDFW, reported in the media, etc.
Many of the (surviving) bats from these large breeding colonies that we have in the South Sound area will disperse across the larger landscape as soon as they become fully independent of their mothers (as will the adults). You might compare this to salmon returning to their natal waters to breed and reproduce, then heading out to the world when ready. This is as if those natal waters have been drained before the salmon smolt left for sea.
--
From: Greg Falxa
Sent: Thu 23-Jul-09 16:16
To: svaland@ga.wa.gov; fraser.karen@leg.wa.gov; jhyer@ci.olympia.wa.us...
Subject: Capitol Lake draw-down's impact to regional bats
Did anyone involved in this decision ask the question "what impact will this have on the region's bats?" I am asking this as a serious question.
After reading the G.A. press release I expected possible dismay, but was shocked to see how little open water remained in Capitol Lake when I went to check out this draw down. I cannot think of a worse time for this to occur; this part of July is the most critical of the energy-demanding time for the many thousands of nursing mother bats which congregate nightly to feed at Capitol Lake. They spend the night feeding here, then head back to their colonies to feed the young. Right now, the young are nearly adult-sized yet still dependent on their mothers' milk. That means they are needing the most resources of any time they are nursing. By this week, a few young might be making their first trips to the lake as well, when they are just learning to forage for insects emerging from the surface of the open water.
Last Thursday at dusk, 3,300 bats exited the Woodard Bay nursery colony; most head directly to Capitol Lake to feed. This is only one of three large groups of bats--that we know of--that use the lake as a primary feeding area during this 'maternity time.' This is not new information; it has been presented by various people many times during the formal and informal discussions about the fate of the Capitol Lake: to CLAMP, to GA, to WDFW, reported in the media, etc.
Many of the (surviving) bats from these large breeding colonies that we have in the South Sound area will disperse across the larger landscape as soon as they become fully independent of their mothers (as will the adults). You might compare this to salmon returning to their natal waters to breed and reproduce, then heading out to the world when ready. This is as if those natal waters have been drained before the salmon smolt left for sea.
--
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