Monday, October 27, 2014

Bad Business for the Bats

Post contributed by Mary, Conservation Corps Youth Outdoors crew member:

As night time temperatures drop below 50 degrees, it is time for bats to hibernate. With hibernation, however, comes a new danger – White-nose syndrome (WNS). WNS is a bat disease that has been rapidly spreading across the United States and Canada. It is a skin infection caused by a fungus, Pseudogymnoascus destructans, which develops over the bats wings, ears and muzzles during hibernation restricting their breathing. This causes the bats to awaken from their deep hibernation sleep, which in turn causes them to rapidly deplete their fat stores before winter’s end resulting in death from starvation. Some bats appear to die directly from the infection as well, so the exact cause of this rapid death is still unclear. WNS, which is thought to have been brought from Europe to a cave in New York eight years ago, has spread to 25 states and five Canadian provinces decimating bat populations. If WNS infects a cave it can wipe out over 90% of the bat population. Bat populations cannot recover quickly from losses such as this because bats usually lead long lives and have only one pup a year.
Photo: U.S. Fish and Wildlife Service via flickr
There are seven species of bats in Minnesota, four of which hibernate as opposed to migrate and are therefore susceptible to WNS. All four of these species, Little Brown Myotis, Northern Long-Eared Myotis, Tri-Color Bat, and Big Brown bat, have been affected by the disease in eastern states. The fungus associated with WNS has been found in two Minnesota caves, Mystery cave and the Soudan mine, but so far bat populations have remained healthy. We hope the 2014/2015 winter will bring the same results because bats are essential to Minnesota’s ecosystems and agriculture and their disappearance could be detrimental. Bats are one of the only predators of night flying insects and consume them in huge numbers. A female caring for her young can eat her weight in insects in one night. Bats help keep down numbers of insect pests who can damage crops, prairies and forests, and not to mention are a nuisance to humans.

We can all help slow the spread of WNS by reporting to the Minnesota DNR any bats that you see flying during the day in the winter; a sign that they have woken up from hibernation and may be looking for food. It is also a good idea to not enter any caves where bats are hibernating as not to disturb them or possibly spread the disease which is thought to enter caves on the shoes and gear of spelunkers. If you do go in a cave make sure to wash your clothes, gear and shoes before and after entering. 

Want to know more?

Wednesday, July 30, 2014

Bluebird Trail Winding Down

Post contributed by Sharon, volunteer bluebird trail monitor:

Five one-week old bluebirds
All is well on the trail this week. The eight week-old bluebirds occupying two boxes appear quite content and healthy. I did not open the box containing five close-to-fledging bluebirds, but caught a glimpse of a beak poking up towards the entrance hole from inside as I passed by. The rest of the boxes remain empty and I will soon remove them, to clean and store them for next spring.

Wednesday, July 23, 2014

All is Well on the Trail

Young male bluebird out on his own!
Post contributed by Sharon, volunteer bluebird trail monitor:

Only three boxes are occupied now on the trail. In those boxes are a total of 13 healthy young bluebirds (five over a week old, and eight recently hatched). The other eight nest boxes remain empty.

Ants had moved into the box with the unused bluebird nest inside it, so I removed the nest (and some ants). Since no new bluebird eggs had been laid in the nest where the four eggs disappeared last week, I removed that nest also.

I was pleased to come upon a speckled young male bluebird perched in a little tree near one of the occupied boxes.

Wednesday, July 16, 2014

Week of the Disappearing Eggs

Post contributed by Sharon, volunteer bluebird trail monitor:

Five bluebirds hatched recently. There were no new fledgings or eggs laid in the past week.
Gorgeous tall grass prairie in bloom,
site of Gilbertson nest box occupied by bluebirds
Unfortunately, there has been a reduction in the number of bluebird eggs on the trail. Four bluebird eggs disappeared without a trace from one box—the nest inside was completely undisturbed and clean. It could be the work of house wrens, though the box is not located near a brushy area (typical house wren habitat).

There are still eight bluebird eggs in two other boxes.

The last tree swallow nest filled with feathers turned out to be empty—no eggs, no birds, no mess—used tree swallow nests end up very messy by the time the young birds fledge. There definitely were eggs in there earlier, but they never hatched—this nest was pristinely clean. The phantom yellow beak in the photograph from two weeks ago must have been the thick blade of yellow grass I discovered when I removed the empty nest. What happened? Perhaps house wrens removed these eggs, too.

Eight boxes are now unoccupied.

Thursday, July 10, 2014

Record Numbers on Como Park Bluebird Trail!

Four new bluebird eggs
Post contributed by Sharon, volunteer bluebird trail monitor:

Three more bluebirds fledged in the past week (19 total) and there are now 17 bluebird eggs in four nest boxes. If all goes well, this year’s totals could be the second highest in the six years the trail has existed. Sadly, I found two young bluebirds dead of unknown cause in the box where the other three fledged.

I did not open the last tree swallow box since the young birds may be too near to fledging.

There are now five empty boxes. Two had small amounts of nesting materials probably belonging to house sparrows, which I removed. Another had a pair of bluebirds defending it, who will hopefully soon build another nest inside. The last box has an empty bluebird nest in it.

Wednesday, July 2, 2014

Bluebirds Begin Second Round of Nesting!

5 new bluebird eggs
Post contributed by Sharon, volunteer bluebird trail monitor:

In the past week nine more bluebirds fledged (16 total so far this year). There are five bluebirds who will likely fledge in the next week, and a new nest with five blue eggs (the first eggs of “Nesting Round 2”). The bluebird nest that contained a cowbird egg (and no bluebird eggs) was empty this week—no egg at all!

Tree swallow nest,
note the yellow beak on the right
At least four and up to seven tree swallows fledged in the past week. The remaining active tree swallow nest, the one I was unable to see into last week, was still very difficult to see into this week. My camera captured what appears to be a yellow beak, and the box felt warm inside, so I am sure there is life in there, but I don’t know how many birds. Could be up to five.

Six boxes are now empty and ready for new nests. One formerly empty box had a small amount of nesting material inside that may belong to a house sparrow.

Wednesday, June 25, 2014

Como Park Bluebird Trail Update: June 25th

Post contributed by Sharon, volunteer bluebird trail monitor:

Seven bluebirds and one chickadee fledged in the past week. Two boxes are now empty and another has what may be a new bluebird nest on top of the old one. The bluebird nest with the cowbird egg in it remains the same—no bluebird eggs have been laid, so perhaps the bluebirds got wise to the intruder and went elsewhere. If there is no change in the cowbird egg by next week, I will remove it and the nest.

In four other boxes there are 14 more bluebirds. I did not open three of the boxes since the young birds are too near to fledging.

The remaining three boxes have tree swallows in them. Two, I did not open, but as I passed I could see two tree swallow heads poking out in one, and another in the second. I could not see into the third box for all the feathers. There were no parents defending the nest, and as far as I can tell, the mother was not camouflaged inside. Perhaps next week will provide a clearer view. If not, a little probing may be in order. (This is the box that was being vandalized two weeks ago.)