During the summers of 2019 and 2020 there has been a substantial loss of life on Christiansen Lake. Normally, at least spanning from the 1980s, there has been a productive, interesting, and diverse resident waterfowl population, and their protection was a primary interest outlined in the Christiansen Lake, Lake Management Plan adopted in 1999. Residents included nesting swans, multiple pairs of common loons, a pacific loon, multiple grebes, mergansers, a variety of diving and dabbling ducks and eagles and osprey. The lake is stocked by ADF&G with Kokanee and rainbow trout. The lake is a stopover for migratory waterfowl as well, with 2017 being an exceptional year as more than a hundred waterfowl staged off the lake, on May 17 and May 18th of 2017, during a late breakup. Many new species visited in the following week, but the nesting summer residents were typical. However, by the end of that season, we noticed a decline in the number of nesting waterfowl. A milky algae bloom was seen on the shoreline during late summer. By 2019, the change was dramatic. A productive family of beavers had left the lake mid-summer, at the height of their construction season. Many of the ducks had left the lake, and only a few pairs of grebes and mergansers, and two pair of loons remained. The leech population boomed. Although we confirmed the lake continued to be stocked by ADF&G, we saw few fish rising, even during insect hatches. In 2020 there was nearly total failure of the nesting population. One pair of loons remained, and failed to produce any viable offspring. One very small pair of grebes remained, and lost all their chicks by season end. An unidentified diver duck pair had one chick survive. The swans, mergansers and other ducks did not return. The eagles that frequently hunted from adjacent trees, and the Osprey had left the lake. Two algal blooms were noted, one a bluish green underwater, and the other a milky grey on the surface near shorelines. The shoreline plant succession during these years changed from common shore bushes to an overabundance of lupine at shoreline, which gave way to water hemlock, which has now become the dominant shore plant around much of the lake. The leech population has exploded. The water otherwise remains clear, but drifting across the lake, it is notable for a lack of underwater life. Other lakes located in the Talkeetna chain of lakes (Christiansen Lake is the northernmost one), which include XY Lakes, Fish Lake, Numbered Lakes, etc. have been subject to the same environmental stress, such as heat, low rainfall, spruce die off and birch stress. We are not aware of any changes with the waterfowl populations on those lakes.
During this same period, a rock quarry was developed adjacent to the lake, with drainage being two culverts that pass under a road and drain into the lake basin. Loud noise and blasting takes place throughout the spring and summer during the nesting season. The area had a substantial die-off of spruce trees due to beetle-kill. The bird population around the lake shifted as well, with more white crowned sparrows in 2019, then to a decrease in sparrows and an increase in nuthatches in 2020. The winter of 2019-2020 saw a dramatic increase in the vole population, while foxes and spruce hens, normally seen regularly, were not seen at all.
According to the Alaska Climate Research Center, annual temperatures in Talkeetna increased by 5.4 degrees Fahrenheit between 1949 and 2016. This warming trend continued in 2017, 2018, and 2019, with annual temperatures reaching above the mean of 39.5 degrees Fahrenheit, established between 1981 and 2010. Annual temperatures reached 36 degrees Fahrenheit in 2017, 37.2 degrees Fahrenheit in 2018, and 39.7 degrees Fahrenheit in 2019. Changes in precipitation are more variable, but are also occurring. Talkeetna receives an average of 28 of rain inches per year, also established between 1981 and 2010. The area received 26.3 inches in 2017, 30.5 inches in 2018 and 25 inches in 2019.
Low precipitation in Southcentral during 2019 coincided with significant wildfires, including the areas around Willow and Talkeetna. Overall forest health changed in other ways, possibly affecting habitat for some species. According to the US Forest Service 'Forest Health Conditions map', Talkeetna has experienced several notable infestations affecting tree health. Between 2013 and 2014, infestations of aphids or leaf rollers contributed to widespread birch defoliation. In 2015, spruce bark beetles began damaging older-growth spruce trees, an infestation that continues to grow across the Matanuska-Susitna Valley. In 2019, another infestation of birch defoliators broke out. 2020 forest health surveys were limited by travel restrictions relating to COVID-19.
Christensen Lake water quality was last analyzed in 2008 during the Cook Inlet Basin Lakes Survey by the Alaska Department of Environmental Conservation. Samples were tested to determine depth, temperature, dissolved oxygen (DO), pH,
conductivity, photosynthetically active radiation (PAR), and fluorescence. In the 2008 Lakes Survey Summary Report (attached in documents), Christiansen Lake did not meet state water quality standards for dissolved oxygen or pH.
The Comsat Road Quarry was developed in 2017 as a materials site used, at least in part, to repair the Talkeetna dyke after it was damaged during a flood. The quarry has operated from 2017-2020 at the opposition of many Talkeetna residents. In an August 2020 article in KTNA, reporter Colleen Couldon Love describes how the lake environment has changed during the time that the quarry has been in operation. The Talkeetna Community Council is working to understand the ecological impacts, and is hoping to engage Borough and State agencies. Documents related to this activity are available from the Talkeetna Community Council. The Christiansen Lake plans and Specs are available in the documents section of this post.
