A Northwoods Almanac for 9/27 – 10/10/24

 A Northwoods Almanac for 9/27 – 10/10/24 

 

Eagles Migrating

            Jerry Crabtree in Hazelhurst emailed me on 9/17 saying, “We witnessed 10 bald eagles congregating and circling high up to the north of our lake. Five of them eventually headed south. Are they starting to migrate?  We have had a pair on our lake for many, many years.”
            Eagles are currently migrating out of the north, and actually migrating began a lot earlier in the month. Hawk Ridge in Duluth had a high count of 234 bald eagles passing over the ridge on 9/2, 189 on 9/7, 99, on 9/6, 86 on 9/8, 71 on 9/9 and 51 on 9/12. And they’re still coming.

            I asked Ron Eckstein, retired WDNR wildlife manager and eagle bander extraordinaire, about where the migration of our local eagle population takes them to, and I was surprised at his answer. Juvenile and two-to-three-year-old eagles fan out, going as far south as major reservoirs in Oklahoma and Tennessee, as well as along major rivers like the Ohio and the Mississippi.

            However, adult eagles– five-years old and older – all stay in Wisconsin, though some may dally on the other side of the Mississippi River in Minnesota. They apparently choose to stay closer to their breeding territories, whereas the younger eagles are more footloose (wingloose?).             Breeding bald eagles return to their nesting territories very early in the “spring,” typically by late February or early March, and are typically on nest, incubating eggs by April 1. 

 

Sightings: Cedar Waxwings and Robins Migrating, Snappers “Migrating” Too

            Mary and I can vouch for the fact cedar waxwings and American robins are currently migrating, because a flock of each one of these species has been in our yard eating every last mountain ash berry, elderberry, nannyberry, and dogwood berry we have. I’ve determined that robins were named as such because they are in fact robbers! I’ve asked them to please leave some berries for our anticipated Canadian winter visitors, the pine grosbeaks and bohemian waxwings. But no, the greedy little devils have taken them all. 

            I laugh at myself for getting mad at them – we did plant the trees specifically for birds to utilize. I just have to accept I have no control over when that happens.

cedar waxwing, photo by Bev Engstrom

            Snappers: Chuck Stonecipher on Circle Lily Lake in Manitowish Waters helped 22 baby snapping turtles find their way across the road on 9/18. Our very warm September has likely made it possible for most, if not all, snappers to hatch out and leave their nests this fall rather than for some to overwinter in their nests. The tiny snappers’ emergence is a migration of sorts, too, albeit far shorter, but not without all the dangers inherent in any migratory journey.

baby snapper, photo by Mark Westphal

 

Aspen Dieback

            Jill Wilm in Presque Isle wrote to me: “I’ve noticed that a great number of the aspen trees have lost their leaves prematurely and the fallen leaves are brown/black/curled and clearly diseased. Any idea what’s going on with them?”

            I almost always refer these questions to Linda Williams, Forest Health Specialist for the WDNR in Rhinelander, who really knows her stuff. 

             Her response: “This year we had a lot of rainfall in the spring and early summer that promotes fungal disease. Very early in the growing season the leaves of many aspen trees were heavily infected by leaf disease. Those leaves remained small and off-color for the entire growing season, although they didn’t develop the typical dead leaf blotches until more recently. It was easiest to see the small leaves and off-color leaves from a distance, especially when trees growing nearby had normal non-infected leaves. The diseased leaves are what you see dropping at this time. 

            “I sent in a number of samples earlier this summer and so far Marsonina Leaf Spot is the primary culprit, with Phylosticta Leaf Disease and Venturia Leaf Blight showing up on a few of the samples. We are still analyzing samples as well, just in case we missed something.  

            “All of these leaf diseases will not kill the tree.  Some trees may have been a little stressed by not having fully functional leaves for the growing season, and those trees may be attacked by Bronze Poplar Borer, which will start by attacking a few branches in the very upper parts of the tree and can kill some of those upper branches, but that damage may not show up until next year. 

            “Next year your trees should leaf out normally. Some of them may end up with some upper branches that die, but overall I anticipate that they should be ok next year. And if we have a more normal amount of rainfall next year we shouldn’t see as much leaf disease.”

 

Freshwater Jellyfish

            Bob McGucken from Mermaid Lake in Presque Isle wrote to me on 9/16: “I have been on this 67 acre (56 feet deep) lake for 26 years now. Approximately 5 weeks ago, I noticed thousands upon thousands of freshwater jellyfish. I have never seen these in the 26 years that I have been on the lake. They were still present as of yesterday. What would cause there to be a sudden explosion of these creatures? Why have I never seen them before?  I spend a lot of time on the water every year, so I am pretty certain that I would have noticed them if they were present in the past.”

         If you’re not familiar with freshwater jellyfish, they are quarter-sized, typically hover in the water column from several inches deep to as far down as one can see, and are translucent with a cross shape on their back. 

range map for freshwater jellyfish

         It’s thought that the jellyfish are one of two species native to China, both of which (Craspedacusta sowerbii and C. sinensis) live in the Yangtze River. Freshwater jellyfish were unknown outside of China until 1880 when the jellyfish were found swimming in a large, water-lily tank at the Royal Botanic Gardens outside London, England. Four years later in 1884, immature jellyfish polyps were found in a stream in Pennsylvania.      

            The earliest record of freshwater jellyfish in Wisconsin was in 1969 in a farm pond in Sauk County where wood ducks are speculated to have carried them to the pond. Since then jellyfish have been found in upwards of 100 different water bodies in the state. The last record I’m aware of was from 2020 in Hunter Lake in Vilas County. These "jellyfish waters" vary in size from tiny ponds to lakes 9,842 acres in size (Lake Mendota) and 236 feet deep (Big Green Lake). 

            Why did the jellyfish just show up this year in Mermaid Lake? The US Geological Service website says this: “Craspedacusta sowerbii more often exist as microscopic podocysts (dormant "resting bodies"), frustules (larvae produced asexually by budding), planulae (larvae produced sexually by the hydromedusae), or as sessile polyps, which attach to stable surfaces and can form colonies consisting of two to four individuals and measuring 5 to 8 mm.”

            Well, that’s a lot of difficult scientific terminology, but it does tell me that when folks ask why freshwater jellyfish have suddenly shown up in their lake, the jellyfish may actually have been there for many years in one of the forms described above. 

         The literature on the jellyfish’s natural history in Wisconsin says to look for jellyfish when lake shallows warm rapidly during spring. The jellyfish emerge in mid-June and are restricted to a narrow band of water temperature between 65 to 75 degrees. If the water surface of a lake becomes warmer than 75°, as some of our lakes do during hot summer afternoons, the jellyfish congregate in deeper water where they can find their preferred temperature range. 

         The jellyfish feed on zooplankton and capture even larger prey, such as water mites and insect midge larvae. Their impact, if any, is unclear. While their preference for large zooplankton could influence zooplankton species structure, no one knows if this is an issue.

         These tiny jellyfish are not dangerous to humans. The mature jellyfish live a few weeks, release eggs, and die.

          

Germany’s Use of Renewable Energy – For the Record

         In his closing statement during the recent presidential debate, Donald Trump made a comment that earned a pointed response from the German government: “You [Kamala Harris] believe in things like we're not going to frack, we’re not going to take fossil fuel . . . Germany tried that and within one year they were back to building normal energy plants.”

         Germany’s Federal Foreign Office responded immediately: “Germany’s energy system is fully operational, with more than 50% renewables. And we are shutting down—not building—coal and nuclear plants. Coal will be off the grid by 2038 at the latest.” 

         Germany’s electricity system has made a steady shift from fossil fuels and nuclear to renewables. Wind, solar and other renewables were 54 percent of the country’s electricity generation last year, an increase from 24 percent in 2013.

         However, outside the electricity sector, Germany has struggled to make a shift away from fossil fuels, including for heating buildings and for transportation. Natural gas is the major fuel used for heating buildings in Germany. The country got the majority of its natural gas from Russia, but phased down those purchases in 2022 in response to Russia’s invasion of Ukraine. They’re now building liquid natural gas terminals to process natural gas imports from other countries.

         The point here is that is that energy use is complex and varies from country to country. As examples, Albania, Iceland, and Paraguay obtain essentially all of their electricity now from renewable sources (Albania and Paraguay 100% from hydroelectricity, Iceland 72% hydro and 28% geothermal). In Scotland, renewable energy technologies in 2022 generated the equivalent of 113% of their overall electricity consumption. Ethiopia produces 123% of its own annual electricity needs. See https://www.iea.org/countries for energy production for every county in the world.

         What is simple about energy use, however, is the need for both major political parties in the U.S. to fully support investment in renewables and actions to reduce carbon emissions. The transition to net zero – the balance between the amount of greenhouse gas that's produced and the amount that's removed from the atmosphere – is reachable and inevitable. The debate has to be about how to execute the conversion as far and as quickly as feasible, not whether to do it.

 

Celestial Events

         For stargazing in October, look after dusk very low in the northwest for brilliant Venus, high in the southeast for Saturn, and for Jupiter rising in the northeast around 8 p.m. 

         Before dawn, look high in the south for Mars.

         The new moon occurs on 10/2. It will be at its apogee – the farthest from Earth in 2024 at 252,597 miles.

         On 10/4/1957, Russia launched Sputnik 1, the first artificial satellite to orbit the Earth. Sixty-seven years later, the most recent figure I can find on the current number of satellites comes from May 2024 – 9,900. 

         On 10/5, look after dusk for Venus about 3 degrees above the waxing crescent moon. How much is 3 degrees? Holding your hand at arm’s length and looking up, your pinkie finger is one degree, while your closed fist is 5 degrees.

 

Thought for the Week

            I cannot pretend I am without fear. But my predominant feeling is one of gratitude. I have loved and been loved; I have been given much and I have given something in return . . . Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and adventure. – Oliver Sacks

 

Please share your outdoor sightings and thoughts: e-mail me at johnbates2828@gmail.com, call 715-476-2828, snail-mail at 4245N State Highway 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com