News
January 2026
Lake ice performs many functions. Those of us who enjoy winter recreation are out skating, ice boating, playing hockey and ice fishing. At the same time this surface ice is providing protection for the aquatic life below, insulating fish, turtles, frogs, invertebrates and plankton from extreme temperatures. Ice helps maintain thermal stratification in lake water by preventing mixing by the wind. The metabolism of many aquatic organisms slows down during this period. The lower water temps and ice prevent earlier algal blooms in the spring- a longer ice season means a shorter algal season.
Some fish species rely on ice for safe spawning. If there is less ice, eggs can be destroyed altering the species present in our lake. Earlier ice-off leads to earlier stratification, altering nutrient cycles and the timing of food sources e.g. plankton that fish depend on. Pine Lake is scheduled for a fishery survey in 2026 by the DNR, comparisons to past surveys should be revealing. If there is less ice in winter, shorelines may be more exposed to erosion with winter storm wave action.
Sadly the number of ice days has been decreasing for decades. Rob Manegold has excellent ice on/ice off data for Pine since 1949. The average number of ice days in the 1950s was 101, in the 2020s it is 71. This reflects similar data followed on Mendota/Monona as far back as the 1850s. We are losing ice days on both sides of the season-later ice on, earlier ice off. This has tremendous implications for algae growth, plankton, turnover, and fish species selection.
All data and graphs, R. Manegold​
December 2025
Winter is here with the need for snow and ice removal. Chloride levels in southeast WI lakes have been rising steadily for decades from urban development and the attendant increase in roads, driveways and parking lots. The use of rock salt and other chloride containing de-icers (calcium chloride, magnesium chloride) to melt ice and snow leads to storm runoff into the lakes. Pine Lake’s chloride levels have doubled since 2006. (See graph under Property Management). The Village has worked to steadily decrease it’s salt use on our Village roadways and will only salt on hills and turns, not flat straightaways. Normal background lake chloride levels are 10- 15 mg/L. Our current level at the deep hole off the island is 53 mg/L measured in June 25 - it was 60 at the Beaver Lake inlet, Why do these level matter? Because this is where lake chemistry starts to affect lake biology. Chloride liberates heavy metals from soil as it runs through our yards. As it hits the lake the saltier water is denser, sinks to the bottom and disrupts the critical mixing/lake turnover. The presence of higher chloride levels in sediment liberates phosphorus, fueling more algae. Diatoms and daphnia are affected at levels lower than this, wetland plants are affected at 55 mg/L and at higher levels plankton and fish diversity are reduced. Other sources of chloride are older water softeners which run off timers instead of volume used and fertilizer runoff. For residents, plow/shovel/sweep the most you can and use the least amount of any de-icer. If traction is required use sand. Learn your de-icing alternatives and use the minimum you can.
November 2025
Late autumn is a good time to work at removing your woodland invasive species. They are easier to spot since many stay green longer (buckthorn, garlic mustard, honeysuckle) or retain their fall color longer (euonymus, oriental bittersweet). Moist soil in between rains may make it easier to hand pull smaller plants and herbicide is more effective this time of year- you can use much less on stump applications with less over spray. Plants are moving nutrients to their root zone so the chemical is carried more effectively to the roots of the plant, with a higher kill rate, lower re-sprout rate. The invasive shrubs like buckthorn and honeysuckle prevent the regeneration of native trees and have fundamentally changed what the understory looks like.
October 2025
Fall North American bird migration is an extraordinary time across Wisconsin. It runs roughly August 15th to November 30th . Timing depends on species and location. Waterfowl and songbirds will cross the state in the millions. On a single night this year, September 17, 52 million birds crossed Wisconsin. Our diverse state habitat (forests, marshes and grasslands) and our site between the Atlantic and Mississippi flyways helps the birds find shelter and food as they move south. We provide a welcome stopover, just another reason to be planting native plants for them to use. The majority will move in darkness.
The Lights Out! Message emphasizes the risks posed to birds by light pollution aka ALAN: artificial light at night. The birds are both attracted and disoriented by artificial light, leading to millions of unnecessary collisions. Turn off non-essential exterior lights form 11 p.m. to 6 a.m.
The Cornell Lab of Ornithology has created a brilliant website, BirdCast, with live migration and forecast tools by state and county. The numbers are staggering and fun to watch as to species, speed, number and heights flown.
BirdCast Migration Dashboard - Wisconsin
BirdCast Migration Dashboard - Waukesha County
September 2025
Unfortunately a new aquatic invasive has been identified on Pine Lake. Amanda Schmitz, AIS Coordinator for Waukesha County was performing an early detection survey and found starry stonewort (Nitellopsis obtusa) in the northeast bay. This highly invasive freshwater alga is native to Eurasia but invasive in Midwestern waters. It can create dense surface mats obstructing boating and overtake habitat by crowding out native aquatic species. It is a distinctive lime green when growing with single cell stems and whorls of branches. It’s submerged star- shaped bulbils are distinctive. It is almost always a hitchhiker, so please when returning your boat to Pine always inspect your boat, trailer, anchor and lines for fragments. If the lake you depart has a cleaning station always take advantage of that. Watch for this on your shoreline and around your pier. It can grow to 2 feet. Familiarize your self with this alga and be looking for it at the landing and your pier, or obstructing navigation.
August 2025
Since inception the Pine Lake Preservation Committee has sought to quantify erosion control around the lake roughly by neighborhood. The scoring is based on the presence of 35 foot buffer zones along a shoreline and tree canopy. Below is the graphic from 2024:
If your neighborhood score is low, talk to your neighbors about planting buffers around your bay etc, increasing shoreline vegetation as a group to limit nutrient and pollutant runoff. DNR grants are available for group shoreline planting projects: Healthy Lakes WI Grants