Just like brown-headed cowbirds (Molothrus ater), common cuckoos (Cuculus canorus) in Eurasia are obligate brood parasites that never raise their young. Cuckoos lay their eggs in the nests of smaller birds that foster the cuckoo chicks as their own. A stark difference between cowbirds and cuckoos, though, is their size. Cuckoo chicks can be 10 times larger than their hosts!
If you’ve been to Frick Park’s Clayton Hill lately you’ve seen a plant blanketing the open area down east of Clayton Hill Loop. Invasive mile-a-minute (Persicaria perfoliata) was thick on the ground and climbing every upright when I took these photos in July.
Even if I wanted to walk through this area I wouldn’t. The plant has thorns.
Invasive plants are discouraging but I have hope they’ll be gone some day. The Allegheny Bird Conservation Alliance (ABCA) is conducting a multi-year project to remove invasive plants from Frick Park.
The restoration area is shown on the ABCA map below.
What’s hard for us to do by hand is easy for Allegheny Goatscape’s goats. They eat anything. Here’s how it works.
Prior to bringing the goats, Allegheny GoatScape clears a fence line and sets up the fencing and a shelter for the animals. The herd arrives at the site and immediately goes to work eating the vegetation. … Once the goats eat through the vegetation on site, they are transported to their next [assignment] location.
I haven’t seen goats at Frick but the fenced area at Clayton East looks like goats have been inside it. There’s a lot less mile-a-minute inside the fence.
Now that the goat project is underway ABCA wants to know how the birds respond and is asking birders to count birds in the four restoration zones per hotspot in eBird. Observations are especially needed during August and September fall migration.
But perhaps they’re forgetting how recently those species evolved from mallards. The Mexican duck (Anas diazi) that occurs in Mexico and the U.S. Southwest was thought to be a subspecies of mallard until 1957.
Mallards are just working on creating new species. 😉
Read more about mixed up ducks in this vintage article: Ugly Ducks
Lake Mead at Hoover Dam, 1998 (photo from Wikimedia Commons)
Lake Mead at Hoover Dam, 2015 (photo from Wikimedia Commons)
It’s hard to remember what we worried about before the coronavirus, but long term water crises provoked by climate change are still chugging along in the U.S. West. The most troubling of these is looming at the Colorado River, the water source for over 40 million people.
Many of the seven western states in the Colorado River watershed are suffering under severe to extreme drought. Of course it affects the river.
Albedo is a reflectivity measure of various surfaces as they reflect sunlight back into space. Snow and ice have high albedo, bare ground and trees have low albedo. Melting snow and ice expose low albedo ground so the temperature rises. As the temperature rises more snow and ice melt. This climate change feedback loop is affecting the Colorado River.
The two photos at top span 22 years on the Colorado River at Lake Mead where Hoover Dam holds back the river. The amount of water in the lake is highly controlled by upstream dams but about 20% of that “bathtub ring” can be attributed to the albedo effect.
On a late July visit to Washington’s Landing (Herr’s Island) I saw two song sparrow families with begging fledglings. Unfortunately the begging youngsters were brown-headed cowbirds, not song sparrows.
Female brown-headed cowbirds lay their eggs in the nests of smaller birds. Each cowbird chick is raised, not by its own mother, but by foster parents of another species. To make matters worse, cowbird parents lurk near the foster nest to make sure their own baby survives. They remove the host’s eggs or kill the foster parents’ young to give their own chick a better chance.
Cowbirds parasitize many species but are especially fond of song sparrows and yellow warblers. Yellow warblers are well aware of cowbird eggs and will “abandon” the nest by building a new nest on top of the old one. Experienced song sparrows get upset but don’t have an immediate solution.
However, song sparrows have a secret weapon — their breeding season is longer. Their first of two to four broods may begin before cowbirds are ready to lay eggs while the last nest starts after cowbirds are done.
In Pennsylvania brown-headed cowbirds stop laying in early July while song sparrows are still going strong. What I saw at Washington’s Landing was this year’s last round of cowbird babies.
(photo from Wikimedia Commons; click on the caption to see the original)
Did I say peregrine falcons? Here’s a view from the high-rise roof. When I took this photo I saw (through binoculars) two peregrines perched on the Cathedral of Learning, one on the north face, one on the east.
Today we’ll be really busy moving from one side of Schenley Park to the other.
The movers come at 8:45am. Gotta run!
(photo by Kate St. John. Moving Day cartoon from Wikimedia Commons, click on the caption to see the original)
It’s been so dry in western Pennsylvania this summer that we find ourselves wishing for rain. Yesterday some areas were lucky. It rained 0.61 inches at Pittsburgh’s airport but not throughout the region. Precipitation is still down -2.24 inches since June 1. Are we in a drought?
The US. Drought Monitor map (28 July 2020 above) shows drought conditions and severity across the country. Pale orange in southwestern Pennsylvania indicates areas of Moderate Drought with short-term impacts (“S“). Yellow is Abnormally Dry.
The map above changes quickly if it rains heavily one day. The Drought Severity Index (Long Term Palmer) map, below, charts prolonged abnormal dryness or wetness and matches what gardeners and farmers are dealing with. Southwestern PA has felt like it’s in a drought and, yes, according to the Palmer Index the situation is Severe. (Black on the map is missing data.)
Our situation in Pennsylvania is mild, though. The real concern is out West where the Drought Monitor is bright red (Extreme Drought) with long term impacts (“L“) and the Palmer Index is dark orange.
West Texas is suffering the double whammy of rampant COVID-19 + extreme drought. Today’s a good day to count our blessings in southwestern Pennsylvania.
Last week in Schenley Park I stopped by the Westinghouse Fountain to see swamp milkweed and a photogenic bumblebee.
My cellphone camera was able to capture it in flight!
As I left the fountain a doe crossed W Circuit Road and walked between parked cars to the woods beyond. A fawn soon followed but jumped back in fear before the cars and stopped in the road. Fortunately there was no traffic. It was joined by a second fawn.
The two approached me (I missed that shot) then turned away …
… and were joined by a second doe.
Eventually they all walked between parked cars and caught up with the first doe.
Schenley Park’s numerous deer aren’t afraid of people but they learn to fear cars at a very young age.
p.s. My cellphone can take nice closeups of bumblebees but fails on deer at a distance.