We spent a couple of hours hiking on the Fish Lake Nature Trail in East Bethel, which is part of the Cedar Creek Ecosystem Reserve maintained by the University of Minnesota. We enjoyed seeing a flurry of late afternoon activity among the avian migrants and residents, although most of the birds were high in the well leafed-out trees.
A beautiful afternoon for a bird walk during perfect spring weather!
It’s easy to be cynical about the multitude of challenges to sustaining life on earth, but there are promising steps toward meeting some of those challenges, and today is a good day to think about them. I posted some of the blog below back in 2016, but the message is even more important today, on Earth Day 2024, when we should stop and reflect on how we impact our world.
Things we worry about — illustrated by photos from past blog postings
Warming climate, rising sea levels, and disappearing coastlines directly threaten human habitation, as well as that of wildlife in those areas.
Violent weather: tornadoes, hurricanes, and thunderstorms with high winds threaten people and wildlife.
Lack of winter snowpack reduces the spring/summer water flow in rivers necessary for grassland and desert plants and wildlife to prosper.
Changes in rainfall and river flow impact fish and invertebrate populations and the wildlife dependent on them.
Rising average air temperatures make the local climate unsuitable for plants (and animals). For example, the Cape Floral Kingdom at the tip of South Africa is doomed if temperatures rise much because there is no more southerly retreat for them.
Rising ocean temperatures, coupled with increased acidity of ocean water due to higher CO2 content threaten invertebrates, such as coral. Coral bleaching (due to the loss of their symbiotic algae) has increased dramatically in reefs all over the world in the last decade.
Habitat loss, as more acreage is converted to farmland, impacts wildlife and native plants, resulting in local extinctions.
Changes in weather patterns affect crop harvest and food production.
The consequences of our actions threaten all life on earth if they are not corrected. In my lifetime I have seen the corrections being made, albeit perhaps too slowly: recycling materials, conserving water, “green energy” technology to reduce carbon dioxide release, reducing chemicals, pesticides, fertilizers, etc. released to the environment, reducing air pollution (I grew up in the smog-filled Los Angeles basin in the 1950’s when it was really hard to breathe in the summer).
We don’t have to wait for technology and policy to solve our environmental problems. Not just today on Earth Day, but every day, let’s think about the global consequences of our local actions so we can be a part of the solution to these challenges.
Birds are capable of some amazing feats of flying and have become excellent models for the design of aircraft. Most birds that can “hang” or remain stationary in air accomplish this by flying into the wind with their wings adjusted to achieve maximum lift and flapping, if necessary, to remain in the same position relative to the ground. This is called “windhovering”. You may have seen examples of this behavior in Kestrels, Ospreys, Northern Harriers, or Caspian Terns that use this strategy to “hover” in place while keeping their heads motionless and searching for prey below them.
The video below illustrates the way birds, a Kestrel, in this case, maintain their position in the air column while keeping their heads completely still. Here, the oncoming wind is sufficient to provide lift so the bird moves its wings very little. When wind speed decreases, the birds must start flapping to stay aloft.
It was interesting to watch several Mexican Jays try to hover in still air as they tried to grab suet from a feeder designed for small birds and woodpeckers. The Jays could hover briefly next to the feeder using a combination of powerful wing strokes, as illustrated in the slideshow below. The sequence starts at slide 1 (the number of the slide is in the lower right corner) and ends at slide 23. My camera was set for 10 frames per second, so this sequence represents a little more than 2 seconds of “hovering” by the jays.
I haven’t seen Blue Jays try this on the suet feeders in my backyard. But if Mexican Jays can do this, Blue Jays should be able to also.
A “couple” of deer wandered into the backyard one evening a couple of weeks ago, and I was struck with how much their interaction resembled a teen-age courtship.
An imaginary conversation follows…
Snow or not, the birds are “springing” into action. Decked out in their newly refurbished plumage, males are returning from “down south” to establish territories and are advertising their stuff to potential mates.
And if this attractive male does everything right, with appropriate attention and head bobbing, etc., he may be acceptable to the female.
In celebration of what is to come in the not too distant future…a shock of green to help you think “spring!”
In elementary school we learned that to get green color you mixed yellow and blue — and that’s just what birds do. There is no blue pigment in birds’ feathers either, but incoming light scattered off air pockets in the feather structures can be reflected to our eyes and appear blue. By adding this reflected light to the yellow light reflected from underlying (carotenoid) pigments in the feathers, the birds are doing just what we did in mixing our paints. This is illustrated below by a Broad-billed hummingbird as it approaches a feeder.
As they say in Eire-land
“May your blessings outnumber the shamrocks that grow. And may trouble avoid you wherever you go.” –Irish Blessing
The birdies seem to think it’s spring — cardinals and chickadees are singing in the backyard. A pair of Cardinals were courting on the tree outside my porch window yesterday morning, even while it was snowing.
Meanwhile…the backyard still looks like this
I haven’t seen coyotes in the backyard for several years, and I’ve never seen a pair of them hunting together.
There are still a pair of foxes in the neighborhood here, although I don’t know where their den is. Usually, coyotes won’t tolerate foxes in their territory and will kill them or drive them away, so I hope this coyote pair decide to move on to another area — I like having the foxes visit with their kits in the spring.
The deer herd has been running through the backyard frequently, but they don’t usually hang around — they’re always on the move…to somewhere else. But a few days ago, the big buck visited, sampled the greenery, and sat down for a nap.
A rhetorical question to ask on this — National Bird Day. They are colorful, sing some pretty (if repetitive) songs, perform amazing aerial tricks, are delicate, fierce, strong, bold, and relatively easy to find and see. Plus there is an amazing diversity of them. They are all around us and we take them for granted, but the world would be a sad place without them. This day was created to raise awareness of the difficulties many avian species face because of loss of habitat, climate changes that put them out of sync with their food supply, lethal chemical added to their environment, etc. The list of perturbations to their normal existence is long and is taking its toll on their numbers. So to honor the Birds, I showcase some of them taken from this year’s photos (some of which were sadly lost in the masses of photos that I took!).
Back Yard Biology 