There is a new ephemeral wetland in the arboretum that we at the Interpretive Center have affectionately named “Lake Linnaeus.” This wetland is nothing more than snowmelt that accumulates each spring in one of the parking lots in front of the Interpretive Center, but combined with the recent rains this puddle has already swelled to fill its usual basin. It will be interesting to see just how large Lake Linnaeus will grow in the coming weeks, as there is still plenty of snow yet to melt and more rain in the forecast. But it will be even more interesting to see how all this recent rainfall will affect the Minnesota River, as well as the Red and Mississippi, as conditions are currently being met throughout the state (persistent rainfall and rapid snowmelt) that encourage large-scale flooding. To say the least, the coming weeks should prove rather eventful.

"Lake Linnaeus" in front of Interpretive Center, 3/11/10.

Here are some other highlights from this week in the Arb:

- Earthworms appearing on sidewalks as ground warms and becomes saturated from rainfall and snowmelt 3/10

- Female Merlin (species of small falcon) briefly observed hunting smaller birds near feeders behind Interpretive Center 3/9

- Small flocks of migrant American Robins seen across campus 3/8

- Good portions of lawns near Interpretive Center and across campus now exposed by melting snow 3/8

Mother Nature is beginning to seem a bit more “springy” as of late. More and more tree buds have begun to swell, most noticeable on the magnolias planted across campus and in front of the Interpretive Center. Cardinals and chickadees are in full spring chorus, the males advertising their robustness to any females that might be listening. American Crows are perching on high points across campus (including the clock tower of Old Main), giving forth rather unmusical “caws” that somehow appeal to the opposite sex. Bald Eagles are pairing off and displaying their spectacular aerial maneuvers high above campus. Even squirrels have notably decreased their presence near the Interpretive Center, which means they’re busily out and about preparing for this year’s first brood.

Here are some other highlights from this week in the Arb:

- Heavy hoar frost on the morning of 3/4 (possibly this winter’s last?)

- Cedar Waxwings feeding on (probably fermented) crabapples in front of Interpretive Center 3/4

Cedar Waxwing feeding on crabapples in front of Interpretive Center, 3/4/10.

- Short-tailed Shrew tunneling and foraging through fallen seeds now exposed by melting snow below feeders behind Interpretive Center 3/4-5

- White-tailed Deer footprint found on edge of Interpretive Center parking lot 3/1 (suggesting a passage the night before)

The forecast for the next ten days predicts high temperatures in the low 30’s by early next week, so we should begin to see some more consistent snow melt as we enter March. The question on most Minnesotans’ minds, of course, is how fast all that snow melt will occur. The Fargo/Moorhead area in the northwest has already begun preparations for another massive flooding event (with good reason), and even the St. Paul airport is concerned that the Mississippi River might overflow its banks onto some of the runways. Here in the Minnesota River Valley there is the usual talk of spring flooding, but with last fall’s rains doing a good job of filling up the river prior to winter there is a bit more concern that melting snow will cause the river to significantly overflow. At this point it all depends on the temperatures we experience in the coming weeks; if the first few weeks of March are consistently in the 30’s and only warm gradually, then flooding may be minor and manageable. But if temperatures take a jump into the 40’s and even 50’s, causing rapid snow melt, then we have a greater reason for concern. Additionally, any rainfall we get in March is likely to exacerbate a flood.

Here are some highlights from this week in the Arb:

- Male (rooster) Ring-necked Pheasant feeding on fallen crabapples about 50 yards south of Interpretive Center 2/22

- American Crows acting territorial near Jones Northern Forest Ponds 2/25

- Fresh Eastern Cottontail tracks surrounding young willows (showing evidence of rabbit herbivory) near Jones Northern Forest Ponds 2/25

Eastern Cottontail tracks near willows surrounding Jones Northern Forest Ponds, 2/25/10.

- Buds showing signs of swelling on several trees throughout Arb 2/24

Remember that rabbit I photographed back in early January (appearing in Arb Sightings 1/7/10) behind the Interpretive Center? Well, he’s been appearing in the exact same spot each afternoon since then, and looks none the worse for wear (although he was a little more camera-shy this time). Even throughout the heavy snows and frigid temperatures, this Eastern Cottontail had no problem finding nourishment and sustenance in its small shelter under the highbush cranberry shrubs. It will be interesting to see how much longer this animal sticks around in that same spot; as the snow begins to melt, I’m guessing it will begin to forage farther from the cranberries and ultimately relocate elsewhere in the Arb.

Eastern Cottontail still sheltering under highbush cranberry behind Interpretive Center, 2/15/10.

Here are some other highlights from this week in the Arb:

- House Finches returning to sunflower feeders behind Interpretive Center 2/15

- Cedar Waxwings roosting in spruces south of Interpretive Center parking lot 2/16

- Red-breasted Nuthatch visiting suet feeder behind Interpretive Center 2/18

- Gray Squirrels acting amorous and displaying courtship behavior behind Interpretive Center 2/16

Mid-afternoon looking southwest from the Interpretive Center, 2/10/10.

In the midst of Monday’s massive snowdrifts and severely decreased visibility, I was able to make two interesting observations from the Interpretive Center. The first was that the gray squirrels which frequent the bird feeders behind the Interpretive Center were literally tunneling through the fresh, powdery snow. The squirrels’ heads would pop up and out of the snow just as a thirteen-lined ground squirrel’s head pops out of the ground during the warmer months; while this sort of foraging behavior isn’t exactly the norm for gray squirrels, it appeared they were rather adept at it. The second observation was of a pair of Trumpeter Swans flying low over the Interpretive Center, apparently heading for the Minnesota River. It was only a fluke that I saw these birds in the first place, as the observation lasted only a few seconds, but sure enough they appeared as two ghosts out of the muted sky. While these large birds breed west of St. Peter in the vicinity of Swan Lake and occasionally overwinter along the river in Mankato, this is the first time they have been seen at Gustavus.

Here are some other highlights from this week in the Arb:

- Adult Bald Eagle flying low over the arboretum near Borgeson Cabin 2/10

- Female Sharp-shinned Hawk hunting behind Interpretive Center 2/10

- Three Gray Squirrels chasing each other in a direct line behind Interpretive Center 2/9

- Fresh mouse tracks in snow outside Interpretive Center’s front door 2/8

Though the landscape remains immutably constant, some of its inhabitants are beginning to sense a change. Birds have begun singing their spring songs on warm days in response to the increasing day length; last week Black-capped Chickadees began their vernal two-note “spring’s here!” choruses, and this week Northern Cardinals have begun to chime in with their jubilant “cheery? cheery? cheer cheer cheer” melodies.

Here are some other highlights from this week in the Arb:

- House Sparrows congregating in flock of around 40 birds in trellis at entrance to Interpretive Center 2/5 (this flock is present year-round)

House Sparrow flock roosting in trellis at entrance to Interpretive Center, 2/5/10.

- American Tree Sparrows foraging in spruces and firs south of Interpretive Center parking lot 2/3

- Pair (male and female) of Red-breasted Nuthatches visiting sunflower feeders behind Interpretive Center 2/1

- Smaller Red Squirrels chasing larger Gray Squirrels (presumably an interspecific territorial behavior) behind Interpretive Center 2/2

It has now been over a month since the winter solstice, which means our days are indeed getting longer. Unfortunately there is a bit of lag time between the solstice and when temperatures will begin to consistently rise, and so photoperiod (day length) doesn’t necessarily correlate with temperature. The good part, of course, is that we’re one month closer to the spring equinox on March 20.

Here are some highlights from this week in the Arb:

- Rooster Ring-necked Pheasant perched in high bush cranberry behind Interpretive Center 1/27

- Cooper’s Hawk hunting behind Interpretive Center 1/25

- Black-capped Chickadee singing spring song “spring’s-here!” behind Interpretive Center 1/28

- Red-breasted Nuthatch coming to suet feeder behind Interpretive Center 1/28

- Gray Squirrels feeding on fallen seeds under feeders behind Interpretive Center (finding it more difficult to make jump to feeders as snow sublimates) 1/28

Gray Squirrel feeding on fallen sunflower seeds below feeders behind Interpretive Center, 1/28/10.

The warmer temperatures (and increasing daylengths) have certainly encouraged our local wildlife to become more active. Many of the birds that had been frequenting the feeders behind the Interpretive Center a few weeks ago are now foraging for natural food elsewhere in the arboretum, and the ones that are still around seem to be making less visits. The gray and red squirrels are as active as ever, chasing each other around tree trunks and making bold attempts to raid the bird feeders. The snow has accumulated so much, in fact, that the gray squirrels are now able to jump from the ground to the feeders–rendering the squirrel baffle useless–without much effort.

Here are some other highlights from this week in the Arb:

- Several overwintering American Robins feeding on crabapples west of Interpretive Center 1/19

Overwintering American Robin in crabapple tree west of Interpretive Center, 1/19/10.

- Several small flocks of Cedar Waxwings feeding on residual European mountain-ash berries 1/20

- Lone American Goldfinch at feeders behind Interpretive Center 1/21

- Eastern Cottontail foraging under highbush cranberry behind Interpretive Center late afternoons daily 1/14-20

On Tuesday morning 1/12, the trees in St. Peter were blanketed in a beautiful silvery shimmer known as a hoar frost. This phenomenon is an example of deposition, which is the changing of something from a gaseous state directly to a solid state (skipping the liquid phase). For a hoar frost to occur, the surface temperature needs to be below freezing (32 degrees Fahrenheit) and the air temperature needs to be warmer. When the air contains water vapor (i.e. it feels wet or humid), as it touches the colder surfaces it becomes solid ice crystals and forms a fine coating on those surfaces, whether they be trees, buildings, sidewalks, or stationary vehicles. Hoar frosts can appear especially magnificent during the morning hours when the sun begins to shine through the ice crystals and the entire landscape is draped in silver; such was the scene in the arboretum on Tuesday morning.

Crabapples draped in hoar frost in front of Interpretive Center, 1/12/10.

Here are some other highlights from this week in the Arb:

- Flock of about 50 American Robins observed flying through Arb 1/12

- Northern Cardinal and House Sparrows drinking melted snow in front of Interpretive Center 1/13

- Cooper’s Hawk hunting behind Interpretive Center 1/14

- Gray Squirrels chasing each other and acting territorially behind Interpretive Center (possibly due to warming temperatures) 1/12

Eastern Cottontail sheltering under highbush cranberry behind Interpretive Center, 1/6/10.

The above photo just about sums up how most of us in southern Minnesota feel about Mother Nature right now. Since the latter half of December, we’ve received several feet of snow and ice as a result of two or three major nationwide winter storms. Accompanying these storms, intensely cold air from the arctic has caused daily temperatures to remain steadily in the single digits to sub-zero range. Today we are receiving another four or five inches as the winds increase, severely decreasing visibility and sending wind chills into the -20’s and even the -30’s. Let’s hope that these temperatures aren’t here for long; indeed, a warm-up is forecast for next week (with highs possibly reaching the upper 20’s!).

For us humans, these conditions equate to dangerous road and sidewalk conditions, higher heating bills, and significantly more time spent indoors. For wildlife, these conditions mean life or death, and only those plants and animals with adaptations to such a cold, harsh environment will survive. Mammals that don’t undergo some form of winter sleep often develop thick winter coats to help insulate against the freezing temperatures. Small birds make more frequent visits to bird feeders to help maintain their bodies’ core temperatures.

Here are some highlights from this week in the Arb:

- Single American Goldfinch at sunflower feeders 1/4 (none observed last winter)

- Cedar Waxwings feeding on fermented crabapples in front of Interpretive Center 1/4

- Overwintering American Robin seen foraging among red cedars north of Borgeson Cabin 1/5

- Gray Squirrels “tunneling” through soft, deep snow behind Interpretive Center 1/6