Summer set in with a vengeance in the Intermountain West through much of June, after some cooling weather and rain at the end of May. Very dry and windy conditions fanned raging wildfires in Colorado, Montana, Idaho, and southern Wyoming during the past month. Somehow, we’ve escaped significant fires in northwestern Wyoming, despite the hot, dry conditions…so far. No two years are alike in this part of the world. The variation in occurrence and schedule of wildflower blooming is particularly intriguing. Depending on the combination of ambient temperature and the timing and amount of moisture, the sagebrush-steppe environment of the Bighorn Basin might be covered with lupine, penstemon, larkspur, prickly-pear, scarlet globemallow, and other brightly-colored native flowers in June. This year, we’ve seen only brief, sparse blooms. Many areas that were awash in color last year are lacking blooms at all this year.
Several years ago, with significant late April rains after a very dry winter, we were surprised to see especially lush growth of bunchgrasses and blooming larkspur, accompanied by a large breeding population of lark buntings! We’ve not seen anything like that the year before or since. I suppose the take-home message is that wildlife (both plants and animals), especially in the arid sagebrush-steppe ecosystem, is truly existing on the edge, with even minor variations in weather resulting in dramatic differences in occurrence, distribution, and abundance of some wildlife species.
This year’s golden eagles
Golden Eagles in our study area began nesting a bit earlier than average this year, and many of the young eagles have already fledged (left the nest). I’ve begun capturing and banding some of the eagles who have left the nest. An early review of our data indicates that rabbit populations were very low early in the year, and eagle nest occupancy and productivity were the lowest we’ve seen in the last four years. More on that after we complete analyses and present our results at scientific conferences this fall. Our citizen scientists, the Golden Eagle Posse, have continued monitoring successful nest sites this year. Here are a couple of excerpts from their recent weekly narrative reports:
From Anne Hay and Richard Gruber on 19 June:
The chick is now about 54 days old. The adult is standing at her favorite perch at the south side of the nest. The chick is out of the nest, down an incline, standing about 6 to 10 feet south of the nest. It is farther back from the cliff’s edge, unlike on Tuesday, and is standing in a safe location. The chick begins to eat at 11 o’clock. The feeding occurs for 14 minutes. At 11:39 a.m. the mother eagle begins to feed on a prey hidden from our view. This continues for 4 minutes when the mother returns to her ‘knob’ perch and the chick follows her. At 11:44 a.m. the mother moves to the north side of the nest and again, the chick follows her. Two minutes later the mother begins to feed the chick on some unknown prey. At 11:53 a.m. the female eagle stops feeding the chick and eats for about one minute. She moves to her knob perch and cleans her beak on the edge of the knob perch. We do see, during our observations, the chick preening and exercising its wings. While the soul may be willing, the flesh is weak…so fledging is still two to three weeks away.
And here is a report from Don Chaffey from the same nest on 01 July:
Since we know first flight for this chick is close, I wanted to follow up with another quick observation. At 6 a.m. no signs of life in nest area—no adults and no chick. 6:15: Adult flew into nest area, walked around area like it was looking for food. 6:20: The new fledgling flew into nest area, started vocalizing, then picked up some leftover food—looked like rabbit. It appears that our youngster has fledged at 63 – 65 days after hatching. It is darker in color than adults now and begging for food at a perch near nest.
We are continuing to keep tabs on the nests that still hold nestlings, and will provide an update for you in a few weeks. Until then, keep observing and keep learning!