Phenology Report, February 7 2023
Happy phenology February! John starts the month with a quick note on weather and climate. The last week of January and first week of February are, historically, the coldest weeks of the year. However, this week is supposed to be pretty balmy!
The warm weather will usher in a few events, if you know what to look for. First, Pileated Woodpeckers will start to target the base of trees as a handy source for re-invigorated insects. Carpenter ants are particularly targeted. As the days lengthen and the sun climbs higher in the sky, the intensity of the light increases. Dark surfaces (like tree trunks, pavement, and debris in the snow) absorb the light’s energy as heat and melt the snow around them. In the case of tree trunks, the heat also wakes up the insects residing inside the tree. The insects start to move around, and the Pileated Woodpecker can smell and hear them: all of a sudden, the base of the tree is sporting large holes and a very happy woodpecker! Pileated Woodpecker holes are quite large: 4-5 inches tall, several inches deep, and 2-3 inches wide. John’s son Martin has a clear memory of finding a Tamarack that had been visited by a hungry Pileated Woodpecker: some of the chips of wood it had knocked out of the tree were 2.5 inches long, a quarter of an inch wide, and half an inch deep. They’re pretty strong animals: I sure couldn’t do that kind of damage to a Tamarack tree, even if you gave me an axe!
The sun must already be strong enough to awaken some of the insects, because John’s friend Anne spotted an excavation in a Balsam Fir this week. John’s earliest record in the Grand Rapids area was on January 29th in 2017. His other observations include February 10th (1993), March 7th (2005), March 26 (2009), March 15 (2010), February 14th (2011), February 13th (2012), February 11th (2013), February 9th (2015), March 3rd (2016), March 25th (2019), February 4th (2021), and March 7th (2022). This means that this year’s observation on February 1st was the second-earliest on (John’s) record!
The warm weather also wakes up larger critters than the ants: skunks! John predicts that we’ll have reports of skunk activity by next week. Male skunks wake up this time of year to mate, and the deep snow persuades them to use the conveniently-plowed roads and sidewalks. Keep an eye (and nose) out while you’re driving and walking- remember that the stinkiest creature gets the right of way! Once the skunks have done their skunky deeds, the males are driven off and return to their dens for a bit.
Any unlucky skunk that gets hit by a car will make a nice snack for the eagles, who will be hard at work rebuilding their nests. Last Thursday, John’s resident Bald Eagles had returned to the nest. One landed inside and checked it out. As February progresses, they’ll bring back sticks and branches to further enlarge and strengthen the nest. Then, just before the female lays eggs, they’ll bring in hay or grass to make a nice soft surface for brooding, hatching, and rearing their young.
On that note, John reminds us that Bald Eagles prefer to build their nests in trees, while Ospreys prefer to build at the top of power poles. Osprey won’t return to the area until mid-April, so watching those pole-top nests is a futile effort this month! Bald Eagles, who are more or less year-round residents these days due to consistent access to open water, begin the nesting process much earlier.
On a walk by the lake the other day, John surprised a grouse! It returned the favor by bursting cover right next to him and making quite a ruckus as it flew away. John’s next four steps flushed up 6 more! “It’s a good thing I didn’t have my shotgun,” John says. “I probably would have ended up shooting a poplar tree or my dog or something, because they were bursting out of the snow everywhere.” John isn’t quite sure what brought them down to the lake. Perhaps they were basking in the warm sunshine! In any case, it’s been a good season for the grouse, and not just because John left his shotgun at home. The deep snow gives them a nice, climate-controlled place to rest and hide from predators, and there has been plenty of food for them all winter long. They (unlike the skunks) love a February full of deep snow!
John “Tree-Watcher” Latimer put on his snowshoes to check on one of the aspens he monitors for his phenology records. It’s a female aspen tree that’s about a half-mile trek through the woods from his house. This time of year, aspens begin to break flower buds: at first, they form little fuzzy structures similar in texture to a pussywillow bud. Then, as the flowers develop, they get longer and start showing a bit of color. Most aspens start to break bud in February (though John has an independent-minded tree by his mailbox that decides to break bud in early January). This year, that means that John had to make the arduous journey through deep snow to check on this female aspen tree. While the tree seems to be alive, thriving, and happy despite the stresses of heavy snow and cold weather, no buds had appeared on the branches yet!
To save himself some work, he took the shortest route to the tree and returned the same way. Along the route is a fence post: while I would have just passed it by without a second thought, KAXE’s Resident Phenologist and Very Observant Human saw phenology at work! The dark fence post and wire fencing was absorbing the energy from the sun and melting the nearby snow. It was a subtle effect, but there was definitely some melting! This is caused by the same process that brings the Pileated Woodpeckers to tree trunks: dark surfaces heat more quickly than pure-white snowdrifts.
Under John’s spruce trees, the same effect occurs under different circumstances. This year, the spruces produced a truly voluminous amount of cones: the red squirrels have their tiny, furry paws full trying to scarf them all down! The results of their efforts are piles and piles of bracts (modified leaves, like the ones that form the scales on pine cones) littering the snow below. “The ground looks like it’s got freckles,” John remarks. “It’s like looking at one of those little Irish boys with the pale white skin and lots of red freckles!” As the sun hits the bracts, they’ll begin to melt holes through the snowpack.
John’s last note for this week concerns some very unlucky voles in a very nice habitat. John’s shovels under the base of his birdfeeder, so there is a 12–15-inch snowbank surrounding its periphery. The snowbank is riddled with holes where squirrels have dug in to access the seeds John’s shovel had picked up and transported, and the voles have built their subnivean tunnels to include easy access to this convenient food source.
Speaking of a convenient food source… John looked out his window last week and saw a Barred Owl swoop down and carry off a vole. Twenty minutes later, it returned and grabbed a second.
Once again, it returned: this time, it perched for about a half-hour on top of the snowbank where the voles were. John didn’t see the final swoop, but he caught a glimpse of it flying off a little while later. It returned again three more times, though John wasn’t able to see the results of the visit. [I’d like to point out that I don’t really think of owls as ‘birdfeeder’ birds, but John’s proving me wrong! It just takes a few extra connections through the food web to get to them.] In any case, the owl definitely caught two voles, and if it had even a 50% success rate thereafter, it probably caught at least four voles that evening! As John notes, that is a pretty efficient conversion of seeds into protein into owl. John concludes, “That’s the phenology show for this week! I look forward to speaking with you again in a week. In the meantime, let me know when the skunk shows up at your house!”
Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).