I’ve previously noticed and commented on Red-breasted Sapsuckers and cold weather as well as speculating on what they are doing in winter around here – so one of things I wanted to do during the recent cold snap was get down to the park and see if any sapsuckers were around.

I didn’t end up making it down there until the clouds returned and temperatures had started to rise, but was still able to find two sapsuckers – the one photographed here was in thee trees between the SJ Hatchery and the Crescent Harbor playground. This bird was doing something I had not seen before – a couple of different times I saw it fly down to the cement wall where the flume water came out of the penstock. It would perch on thee cement near the water and appeared to be drinking (see photos below). No doubt they need water, but I wonder if they usually can get enough from the sap they consume. In any case, it was interesting to watch this new-to-me behavior.

The kids and I braved the wind to walk down to the park and see what might be around. I thought the gusts of wind pushing spray across the bay was particularly interesting.

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Red-breasted Sapsucker along SJ Hatchery outflow.

Red-breasted Sapsucker along SJ Hatchery outflow.

Pacific Loon along Sage Beach.

Pacific Loon along Sage Beach.

Pacific Loon along Sage Beach. This bird seemed to have an injury or abnormal growth just behind its head.

Pacific Loon along Sage Beach. This bird seemed to have an injury or abnormal growth just behind its head.

A lone male Common Goldeneye was riding t he waves.

One of the buoys marking the tideflats at Totem Park was taking its share of waves.

Wind-blown spray blurs the view across Crescent Bay.

From time to time an especially strong gust pushed spray across the water.

Indian River from bridge in Totem Park.

Ducks taking refuge from the wind close to shore.

A male Gadwall was hanging in with the Mallards at Totem Park.

Red-breasted Sapsucker on alder tree near SJ Hatchery.

Red-breasted Sapsucker on alder tree near SJ Hatchery.

20110505_RBSA_Lincoln_Street_Drumming.mp3

Been pretty swamped with work and house issues, but have made a little time to go look for spring migrants. This morning on the way back from Totem Park (where there are still lots of shorebirds) I recorded this short clip of a Red-breasted Sapsucker drumming on a metal roof.

The Dolly Varden have started to show up near the beaches again. Rowan and Connor have been fishing for them this week, and Rowan managed to catch a 14″ Dolly (her first) this morning.

I noticed three Red-breasted Sapsuckers engaged in what I take to be courting behavior. They flew between various trees and utility poles near the corner of Jeff Davis and Sawmill Creek Road. They checked out some of the holes on the utility poles and seemed to be following each other around. Unfortunately I didn’t really have time to stop and watch them for an extended period, but my guess is two of them will pair up and nest in one of the two utility poles where there have been nests in several prior years.

On the way to UAS, Connor pointed out a dandelion flower. It was the first fully blooming flower I’ve seen this spring. (I’ve previously noted blueberries and skunk cabbage, but the flowers weren’t completely open at the time).

Temperatures have been significantly warmer since last weekend. It’s been a little strange since even though the temperatures are up in the mid-40s, it doesn’t always feel warmer. I suspect it has something to do with the on-going breezes and the increase in humidity that tends to put a chill in the air. Despite warmer temperatures and some rain, the only the surface of the ground has thawed. While the ice remains below, the top layer gets over saturated with moisture and puddles form or the dirt can become a bit soupy. If temperatures remain this warm, I imagine the ground will thaw out before too long.

I’ve not done a lot of birding lately, but have noticed the first spring migrants in the form of increased gull numbers. It’s possible some waterfowl have begun to move as well, though I’ve not been looking in places where that would be clear. Some mornings around the house the bird activity has been quite high, with many Varied Thrush calling, and a Pacific Wren singing down the hill to the east-northeast. A couple of days ago I noticed a Red-breasted Sapsucker working over a Mountain Ash – the first time I’ve seen a sapsucker on a deciduous tree this year (they focus on conifers in the winter).

I haven’t seen a deer in the neighborhood for quite a while, but Connor said he saw some tracks at the edge of a pile of sand down at the base of the hill to the southwest of our house.

I haven’t noticed much in the way of spring plant emergence other than domestic plants (crocuses, snowdrops and rhubarb). Given the warm temperatures of late, I imagine the first blueberries will be blooming shortly.

Most active were the Pine Siskins – they were chattering from the trees to my east and southeast. They’re fairly aggressive and noisy at most times, but they seem to be spreading out a bit – perhaps they’re starting to separate into breeding pairs. The juncos were also chittering amongst themselves, with an occasional trilled abbreviated song thrown in. They were also mostly to my east and southeast, though lower down in the trees. I saw them flying over the house to south of me as well. Chestnut-backed Chickadees were regular, but less frequently calling, I’m not sure if they were just passing back and forth, actively feeding, or something else. A couple of times down the hill a little further off to the east, I heard a Winter Wren singing. Varied Thrushes gave a few short-quiet buzzing-calls, though mostly they were quiet (I did see one fly up to an upper tree branch when I started walking back to the house).

There were ravens calling in the further distance, and also at least one raven (possibly more) flying over the area repeatedly (though not in any pattern I noticed) making a call I find reminiscent of a shorebird. It’s kind of a rapid “tu-tu-tu-tu” or something like that. I’ve heard them make it in the past, though right now I can’t remember if it was only in the spring time or not. I did see a second raven carrying what appeared to be nesting material yesterday – so I’m curious if the call is something related to courtship/breeding.

When I first sat down at the tree I didn’t notice any sapsucker wells. This seemed odd, since the warmth of this location seemed like a good prospect to induce sap flow. It did not take much specific looking to find several wells tapped in the tree – most of them closer to the base, almost even into where the duff was covering the start of the roots. Most of the wells looked pretty dry, but I did notice more than one with small beads of sap starting to form.

At one point during my sit, I heard a squirrel alarm from the trees ESE of me, then some scurrying in the brush and leaves a short distance directly to my east. I looked over and startled a squirrel that had come down from the trees and started toward me along the ground. It jumped back to the nearest tree, climbed up to get a better look at me and then proceeded to take a detour, jumping from branch to branch and crawling along above my head. A short time a later, a second squirrel did the same thing, though this one took some time to check me out further from the trunk directly above my head. It came towards me head-first, then backed up, shifted a little bit to the side, seemingly trying to figure out who/what I was. After a few moments, it must have decided I was no longer interesting, as it returned to its former quest of chasing the first squirrel (or so it seemed to me). A few minutes later they both came running back toward the direction they had come from, with one in close pursuit of the other.

A substantial bit of melting occurred with ice on the ground through the day, but as soon as the sun was down near the horizon, it started to freeze up and become quite slippery. I actually found it kind of fun to slide down/along icy patches, but it can be treacherous.

Walking down along the harbor about 45 minutes after sunset, I enjoyed the thumbnail crescent of the moon with a bright Jupiter (I think) nearby. The lingering colors of the sunset were reflected in the harbor’s calm waters along with the harbor lights now starting to turn on. I noticed the silhouette of a Great Blue Heron standing at the water’s edge – as we approached, it’s head smoothly turned so it could keep an eye on us; suddenly twisting rapidly to look with the other eye when we had walked past it. I stopped briefly to look at it and see if it would fly off, but apparently that was not enough of a break from accepted human behavior to make it decide to move locations.

Sapsucker weather continued today, though it did begin to moderate. Temperatures reached the mid-20s, warm enough that the sun warmed ground was sufficient to start melting ice along the roads and sidewalks. Forecast is for increasing wind and cloudy conditions with temperatures still remaining chilly, but not nearly so cold as over the past few days. While out today, it seemed like the predominant wind was out of the east, though it was a bit swirly – a couple of times I was hit by small gusts coming out of the west. It also seemed as though on the water waves were coming partially out of the south.

I went on a walk around the park to get to the Post Office. I was curious about how many sapsuckers I would find. I don’t have the count handy, but I think it was at least 10 between the house and the end of the park near the river mouth, plus an additional couple later in the day that I saw in the neighborhoods around the new house. The tide was up during my walk and I noticed Mallards and Barrow’s Goldeneye were feeding quite close to the shore along the rocks at the northwest end of the little sandy cove between Merrill Rock and the bed rock out crops before Sage Rock (this was in addition to another 50 or so Mallards sleeping on gravel at Sage Beach). It’s not unusual to see Mallards close in like this, but I don’t often see Barrow’s Goldeneye feeding quite so close to shore.

Crossing the river, it appeared the ice was starting to collapse and the river was running higher. Given the still below freezing temperatures, this seemed a little odd and I didn’t think the tide was high enough to push quite that far up the river. Perhaps I should have checked out when temperatures were still down in the teens. Quite a few Varied Thrushes were foraging along the river banks, while one American Dipper was splashing about in the open water in the center of the river.

On my return from the post office, I noticed something running across the street in front of the drive to the lower park parking lot. I suspected it was a cat, but didn’t get a great look before it was out of sight behind a house. I decided to investigate more closely and found that it was a cat. It had caught a sapsucker (no doubt when it was at the base of a tree tapping – they’re not accustomed to cats as predatory threats, I suspect). I heard a squeak or two from the sapsucker and approached to investigate more closely. The cat was distracted by me, and the bird took the opportunity to roll upright and take flight, returning to the spruce trees near where it had been captured.

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Part of a group of Barrow's Goldeneye observed in front of Merrill Rock.

It's been cold enough for ice and slush to form and persist along the shoreline.

It's been cold enough for ice and slush to form and persist along the shoreline.

Wind shaped snow adds texture to the surface of the mountain slopes.

Walking across the yard this afternoon, I noticed a Red-breasted Sapsucker working at the trunk of a Western Hemlock (Tsuga heterophylla). I was reminded that this sort of weather (perhaps especially at this time of year) makes for good opportunities to look for sapsuckers. They winter here in limited numbers, though I more often see them at mid-elevations than at sea level. However, when temperatures drop into the 20s and teens they will show up at sea level, especially near shores with sizable trees and good southern exposure. At such times they will really work at the base of the trees, I imagine because it’s the first place the sap will run – perhaps even when air temperatures are quite cold if the trunk is sufficiently warmed by the sun. When I saw it, this particular sapsucker was checking out wells that had evidently been made over the past few days. After it flew off, I checked them out, and they appeared to be pretty dry.

Winds were down today, though there was still a little bit of breeze. Temperatures warmed slightly, and are forecast to warm further over the rest of the week (though the wind is supposed to pick up later tomorrow). Some clouds were evident to the south and west as I walked home from UAS – the sunset was quite colorful, perhaps because of those clouds. On the way to UAS I noticed a somewhat strange looking cloud that appeared to be over Indian River Valley (though it’s difficult for me to say exactly). It was very smooth and I’m thinking that was probably due to wind sculpting. It was also quite isolated, so I’m curious as to what may have led to its development.

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Red-breasted Sapsucker working on a Western Hemlock (Tsuga heterophylla).

Red-breasted Sapsucker wells in a Western Hemlock (Tsuga heterophylla).

The cloud seemed a little strange to me. The shape is might be due to wind sculpting, but I'm not sure why it formed there all alone.

Fairly easy to find around Sitka during spring and summer working their sap wells, Red-breasted Sapsucker abundance seems to drop in the fall and they are rarely reported from November through February along the road system. Most times when sapsuckers are seen, it is during periods with extended below freezing temperatures. At such times, they are most often found in forests with good south facing exposures (Totem Park being a good example). In the absence of any observations, it would be easy to imagine that these birds migrate south for warmer locales, and I suspect that is true for most of the birds that breed in the area. However, given the pattern of winter sightings over the years, it seems that some sapsuckers do spend the winter here, though apparently hiding somewhere they are not often noticed except during cold snaps.

I enjoy hiking the hills and mountains around Sitka, but over the past several years I have made it up relatively high only once or twice per winter. Somewhat surprisingly, on several of these hikes I have seen a sapsucker at moderate elevations (I’m guessing between 1000ft and 2000ft). Although this constitutes only a handful of observations, the fact that it occurred on a relatively high proportion of opportunities suggested that sapsuckers may be hanging out at mid-elevations throughout much of the winter, at least around Sitka.

Although my experiences finding sapsuckers led me to believe that they were likely to be spending winters in mid-elevation forests, I was puzzled because I could not figure out why they would prefer this habitat over lower elevations where conditions are less harsh. Adding to the mystery is that I do not remember seeing sapsuckers at mid-elevations much, if at all, during the spring and summer. I associate them almost exclusively with low elevations in forests near shorelines or valley bottoms, generally below <500 feet, and mostly closer to sea level than 500ft. A couple of weeks ago on my annual trek of Mt. Verstovia for the Christmas Bird Count, I once again found a Red-breasted Sapsucker working a tree at about 1500 feet or so. I watched the bird tapping at the well on the trunk of a moderate-sized Sitka Spruce, and for some reason I thought I remembered reading or hearing that getting sap to make maple syrup works best when nights are below freezing and days are above. I could not remember where I got this information (or if I had confused it somehow), so when I got home I took a look on-line. According to wikipedia’s article on maple syrup production, “Freezing nights and warm days are needed to induce sap flows. The change in temperature from above to below freezing causes water uptake from the soil, and temperatures above freezing cause a stem pressure to develop, which, along with gravity, causes sap to flow out of tapholes or other wounds in the stem or branches.”

The way I read this, sap flow seems to be a matter of physics more than anything special about the maple trees (though the same cannot be said of sugar content!). Freezing nights and warm days result in greater sap flow than consistently warm (or cold temperatures). This suggests a plausible reason that sapsuckers would prefer the mid-elevation forests over the warmer lowlands – at those middle elevations, temperatures are more often below freezing at night while warming sufficiently during the day to provide a more abundant food source for the birds.

It should not be too hard to test the temperature and sap-flow part of this hypothesis, a handful of ibuttons and a tap or two to collect sap ought to do it. (It would also be interesting to know whether the winter birds are individuals who also breed here, though that would be more challenging to determine, I suspect). Perhaps one of these winters I’ll give it a try, but in the meantime this is the best explanation I’ve been able to come up with for the somewhat unexpected behavior of Sitka area Red-breasted Sapsuckers in winter.