Hot, dry, and smoky

Minnesota has progressed from the swampy, humid weather of Florida to the hot, dry, and smoky weather of California, as the huge fire burning on the Canadian border north of the Boundary Waters Canoe Area propels its smoke in our direction. The air quality last week established new records for most particulate matter ever, and the skies reminded me of the ones I saw in Los Angeles during the 1950s when 3rd degree smog alerts were common. Added to those depressing conditions is the fact that three-quarters of the state has been officially categorized as suffering severe to extreme drought. Watering lawns is highly discouraged.

But the birds don’t seem to mind…yet.

At the Grass Lake slough, a smoky haze hangs low over the landscape. Wildflowers have bloomed in spite of the drought, but they are less abundant and much shorter than they were last year at this time.

Even though the water level in the slough is down quite a bit, there are still a few fish to catch. And the young Green Herons are pretty good at finding them.

Why are some birds so common — Part 3

In previous posts, I made the case that some bird species adapt well to the human urban/suburban landscape, increasing in numbers as they make use of the rich resources of our gardens and backyards.  Other species, not fussy about where they live, what they eat, or how inclement the weather have also increased in numbers in our backyards because they are generalists whose survival strategy is simply to make use of whatever is available.

Everyday birds — common for several reasons

A third and more recent influence on the local abundance of particular birds is the changing climate in the last 100 years. Not only has the average winter temperature here in Minnesota increased 4-6 degrees F, but the winters are shorter, less snowy, and more unpredictable in severity.

Two species in particular have responded to that warming trend:

It’s hard to believe that Northern Cardinals and American Robins haven’t always been common in our Minnesota backyards.

A monograph published in 1916 by Thomas S. Roberts MD for the Minnesota Geological and Natural History Survey listed Cardinals and Robins as “accidental” occurrences in Minnesota during the winter.  Dr. Roberts even stated:  “Records of the occurrence of this common cage bird [Cardinal] are always open to the suspicion that the individuals seen are escaped captives.”  In 1916 there were just two dozen records of Robins having been seen in sheltered locations in southeastern Minnesota.

Two other common residents of our backyards most of the year, Crows and Goldfinches, were listed by Dr. Roberts as mere “visitors” to the Minnesota winter landscape, being rare occurrences 100 years ago.  Of course it may not just be a response to changing winter climate that has caused increases in numbers of these birds.  Goldfinches are attracted to backyard bird feeders, which makes it easier for them to find sufficient food in the winter.  Crows are adept at avoiding cars while feasting on road-killed animals, and there certainly are more of those than 100 years ago.

Goldfinches are one of the most common visitors to my bird feeders in the winter.

The northward expansion of bird species includes migrants coming from tropical areas as well.  For example, Blue-winged Warblers and Orchard Orioles migrate much farther north to breed than they did 100 years ago.  In fact, because of their northward expansion Blue-winged Warblers now encroach on breeding areas of closely related Golden-winged Warblers and may be a cause of marked population decrease in Golden-winged Warblers.

Orchard Orioles have expanded their breeding range northward into southern Manitoba and westward into Colorado.  The birds feed on nectar, pollen, and insects so perhaps they have found an open niche in shrubby areas with plenty of flowering plants in northern latitudes in the summer where temperatures are more amenable and food is more reliably available.

Northward expansion includes birds moving their year-round residence from tropical areas that are heating up to cooler areas in northern North America.  For example, there were no Great-tailed Grackles north of the Mexican border except in southern Texas in 1934. Steadily moving north, they reached southern Arizona, then Houston, Oklahoma, California, on to Missouri and Nebraska, and finally Iowa by 1983. The species has become a common sighting throughout a vast area where it was completely unknown a century ago.

I went to south Texas to see (and photograph) this bird, but it’s just a short hop from Iowa to Minnesota, so we should expect to see them here soon.

The real problem with this northward expansion of breeding and winter ranges of birds is that birds use the changing photoperiod (daylength) to time their annual cycle and come into breeding condition, but the plants and insects on which they rely to sustain themselves and raise their chicks depend on the temperature cycle of the local area — which may not necessarily be synchronized with photoperiod.  In a warmer year, insect and flower blooms may take place before birds arrive at far northern latitudes, and birds may not have the resources to produce young that year, or even sustain themselves for their southern migration.

Here’s an interesting read on the subject from Audubon.

The hills are alive…

Winter rains bring the California oak woodland back to life, with the greenest of green grass and herbs carpeting the oak understory.

Oak woodland makes up the landscape along I-680, in the east bay region of Northern California.  

The hillsides are a mosaic of coastal live oak, an evergreen species that retains its leathery leaves, and the deciduous valley and blue oaks whose bare limbs reflect the gold light of the setting sun.

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Drought-tolerant Blue Oaks are often found on hill tops, whereas Live Oaks populate more mesic north-facing slopes and lower hillsides near water.

The winter rains seems to have arrived a little earlier this year.  Early rainy weather usually doesn’t fool these deciduous species; they won’t leaf out again until late February, after they have flowered.  At least that’s the way it is supposed to work.

However, unpredictable climate changes can disrupt normal patterns, leading to insect blooms before avian migrants return, or plants flowering before pollinators are present.

The long-term effects of aseasonal rain/drought on the oak woodland ecosystem here are unknown, but it’s been nice to hike in the cool weather and gorgeous scenery of the rain-soaked hills of the east bay region of Northern California.

Earth day — challenges and hope

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.  As a start, check out this commentary on CNN this morning.  Efforts made to reduce the steep rise in average global temperature are happening on a variety of fronts — such as 155 countries signing the Paris Agreement on Climate Change today!

Things we worry about — illustrated by photos from past blog postings

Warming climate, rising sea levels, disappearing coastlines…

Violent weather: tornadoes, hurricanes, thunderstorms with high winds

Lack of winter precipitation snow pack reduces the spring/summer water flow in rivers…

Changes in rainfall and river flow impact wildlife populations

Rising average temperatures that make the local climate unsuitable for plants (and animals). 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…

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…

Preserving habitat AND wildlife for future generations

Not just today, but everyday, let’s think about the global consequences of our local actions to be part of the solution to these challenges.

a blast from the past

I’m busy with Christmas craft creations and have been neglecting the blog. It was exactly 0 F this morning (brrrr….) when I got up to make the first cup of coffee, and I couldn’t help but reflect on past November 17s, which are fortunately recorded in this blog.

The backyard has now accumulated about 6 inches of snow on this date in 2014, but cold weather makes it unpleasant to romp around in it.

Last year on this date:

One year ago today…the leaves hadn’t completely fallen, fall color was fading, temperatures were moderate, and Minnesotans were wondering where winter was.

Last year, we might have been thinking about global warming here in the upper Midwest, as fall went on and on.  But be careful what you wish for, because of course, we then endured the fourth coldest winter in MN recorded weather history with 50+ days of low temperature below 0 F.  So much for the warming trend here.

Two years ago on this date:

Two years ago on this date, ducks were thick on Minnesota lakes, with huge rafts of Goldeneye, Bufflehead, Hooded Mergansers, Scaup, and Ring-necked Ducks.

Duck migration happened a lot earlier this year than two years ago.  A week of overnight lows in the single digits froze much of the open lake water this past week, and the ducks are now gone from the local small lakes. Only the mallards stick around when the weather gets this cold.

Three years ago around this date:

Three years ago, the deer herd in the backyard numbered at least 9, down from a previous high of 16, seen on Thanksgiving a couple of years earlier.  I could easily find them in the wetlands behind the backyard, as they munched on the the green stuff remaining at this late date in the fall.

The prolonged cold weather last winter was very hard on the local deer population, and the does that survived the winter may not have had enough energy to reproduce.  I haven’t seen a doe in the backyard since early this past summer, and she had just one fawn with her.

I have enjoyed many things about blogging:  “meeting” people from all over the world through the blogosphere, learning about photography, becoming a much better naturalist, etc.  But an unintended benefit from recording day-to-day activity in the backyard is an appreciation of how much the backyard and the diversity of life there changes from year to year.

Rainforest in Minnesota?

A three day drenching after a long two-month rain drought turned our dehydrated deciduous forest into a dripping rainforest.  Walking through Reservoir Woods the other day on a cool, but humid morning, I felt like I was in Tacoma, Washington instead of Minnesota.  I hope the photos below can convey some of that scene.

It’s amazing how fast the ferns and the moss perk right up after a hard rain.

Not really a rainforest, but looks like it. Moss was growing on the north sides of the trees (opposite where I was standing).

No fall color in this part of the woods — yet.

Fungi are notable for their rapid growth. I have no idea what this one was, but clumps of it had invaded several parts of the trunk of this still-living tree.

Some of the mushrooms had grown quite large.  This was one of three giants in an area where there weren’t even any fallen logs.

Would Minnesota develop into temperate rainforest characteristic of the far northwestern coastal areas of North America (click here for a map of the global distribution of temperate rainforest)?

Real temperate rainforest in Victoria, BC, Canada.

Most likely not.  Average rainfall in MN is about 32 inches; average rainfall of a temperate rainforest is about 55 inches.  Climate change models predict that the MN climate will become more like Kansas than Washington state — warmer and drier, not cooler and wetter.

But it was nice walking around, pretending for a day.

Timing is everything…

Last year we had an early spring (and not much of a winter), so the butterflies arrived and the bees appeared well before there were flowers to pollinate, or even leaves present as food sources for larvae.  Things were out of sync — badly, and I’m sure the insect populations took a nose dive in Minnesota as a result.

Last year, Monarch Butterflies were faced with laying their eggs on 6-8 inch tall plants. This photo was posted on May 12, 2012.

This monarch caterpillar tried to complete its development on this tiny milkweed, which was growing too slowly to keep up with demand. Ultimately, the caterpillar failed to metamorphose to a pupa.  This photo was taken June 26, 2012, and posted here.

This year, spring was 4-6 weeks late here, and also late perhaps further south of us as well.  We are well into summer, the flowers blooms are peaking in home and natural gardens, but pollinators are rarely found.  My raspberries have bloomed and set fruit, and yet I never saw a bee on the flowers the entire time.  Bumblebees are mostly absent, wasps are a rarity, honeybees and other small bees almost entirely absent.  We do have a lot of bee-mimic hoverflies (Syrphidae) though.

So, I was delighted to find a female Monarch butterfly in the backyard (first one this year!), depositing her eggs on a swamp milkweed plant.  The flower heads were still a couple of days from opening, but she was not trying to insert her proboscis into them anyway (proboscis is tightly coiled in the photo).

She probed the flowers and leaves repeatedly with her antennae (to determine whether it was in fact a milkweed plant?).  The proboscis is coiled up under her head.

Several times I saw her purposely lower her abdomen below wing level underneath a leaf, so I assumed she was laying an egg there.  When I checked those leaves,  sure enough, there were some little cylindrical eggs sticking up from the under surface (one per leaf).  I would have taken a photo, but they were much too small for my telephoto lens.

You can see the curvature of her abdomen better in this photo, and even imagine that there is a little white something being extruded from the tip onto the undersurface of the flower umbel (this is pure conjecture — I don’t know that they would lay an egg in a flower cluster).  Click on the photo for higher resolution of the abdomen.

I haven’t seen many photos of butterflies posted on the various blogs I read, so I wonder if this drought of butterflies is widespread over the U.S. (or other parts of the world) this year.  There are strange climatic swings everywhere that may well influence the insect populations (drastically), and that, in turn, would be devastating for our food production.