This summer has been a very quiet year for monarch observations in Minnesota and Wisconsin. The reasons for this drop in Monarch numbers are two-fold. Last winter the number of Monarchs over-wintering in Mexico was 80 percent below average due to the high heat and drought last summer. The late and cold spring this year also delayed the Monarch’s northward movements, meaning that fewer Monarchs will complete the season’s fourth breeding cycle. What does that mean for the future of Monarchs? These amazing insects have high breeding potential and a widespread range so their population may recover. However, multiple years with low breeding success could signal a big problem for these amazing migrants. To read more about Monarch migration and population studies please visit Journey North .
As a teaching orchard we have a special fondness for pollinators. The population declines encountered by Honey Bees and bat species are frightening. These small creatures are responsible for a huge proportion of global pollination. Bats also play key roles in seed dispersal and pest control. Read on for the latest news on their struggles.
The primary cause of decline in bats is White Nose Syndrome. Healthy forests need healthy bats. Sadly millions of bats in the Northeast have already been killed by White Nose Syndrome. The fungus is moving southward and westward towards Wisconsin and Minnesota. Today there is some good news. In some of the caves struck by the syndrome there are small populations of survivors. You can help bats through Citizen Science efforts and by providing shelter in the form of bat houses. This fall the USDA Forest Service produced a short video about the difficulties faced by bats in North America and the work to save bats.
Those following the search for a cause of Colony Collapse Disorder and a solution to the problem which causes a 30% die-off of bees annually will enjoy this video. University of Minnesota’s bee researcher Marla Spivak presented a TED talk on some of the factors that contribute to the problems that Honey Bees are facing. She also presents some simple things we can do to help bees, which are as easy as planting native flowers. For more on our bees watch her fascinating presentation here.
In recent years more than 160 species of amphibians are reported to have gone extinct worldwide. Scientists are searching for answers and recent evidence from Chicago’s Lincoln Park Zoo and Northern Illinois University points to buckthorn as one of the problems. Invasive European Buckthorn emits a toxin called Emodin from its leaves, bark, roots and fruit. Emodin is toxic to developing amphibian embryos. The highest level of Emodin in the environment is during leaf-out, which coincides with the peak early-breeding activity of Midwestern amphibians.
What can YOU do? November is a great time to spot buckthorn growing on your property as they are one of the only trees that will retain green leaves at this time of year. To read more about buckthorn, how to recognize and eradicate it please see the resources available at the Washington Conservation District and the Minnesota DNR .
For over 113 years, tens of thousands of birdwatchers of all skill levels spend one day recording all the birds they see and hear.
The Christmas Bird Count is the longest-running citizen-science wildlife census and it has provided valuable insight into changes in bird populations over the past century. The study documented nationwide declines in bird species such as American Kestrels and Northern Bobwhite Quail. The survey has also recorded the incredible expansion of House Finches across the continent and more recently the expanding range of Eurasian-collared Doves.
The methodology is that the observers must be within a 15 mile diameter circle and the count date must take place between December 14 and January 5. There are over 2,300 established count circles across the United States and Canada. Carpenter Nature Center is part of the Hastings-Etter count circle and our count date is December 28th.
If you are interested in taking part in this year’s Hastings-Etter Christmas Bird Count, please contact Jen Vieth.
Early winter mornings often are blessed with three suns; the true sun and two false suns located on the sun’s left and right. The bright spots are referred to as Sun Dogs or Phantom Suns. The scientific word for this natural phenomenon is parhelion (plural – parhelia) which originates from Greek and means “beside the sun”.
Sun Dogs are created when sunlight refracts off thousands of plate-like, hexagonal ice crystals floating in high, cold cirrus or cirrostratus clouds. Thinking back to science class you may recall how light ‘bends’ after passing through a prism. Sun Dogs are commonly observed when the sun is low in the sky on a chilly morning, but in perfect conditions, the Sun Dogs will follow the real sun up into the sky, like a dog following its master. The orientation of the ice crystals determines whether or not a Sun Dog will appear. When the ice crystals are aligned randomly in the air, the refracted light forms a glowing ring around the sun called a Halo. As the ice crystals fall downwards through the air they align horizontally and the refracted light forms Sun Dogs.
During very cold weather, such as we’re feeling lately, the ice crystals drift through low-level air creating Diamond Dust which also refracts the sun’s light. Believe it or not, even a bright moon will have a similar effect, forming false moons called Moon Dogs or paraselenae.
Hundreds of bird species call the Midwest home at some point in the year. Each species has its own system to survive the winter. Ospreys leave the area and head to Central or South America. Great Horned Owls are well-equipped to endure our cold temperatures and stay on their territories. Did you know that the Midwest is the southern destination for some birds? Snow Buntings, Lapland Longspurs and American Tree Sparrows all head south to Minnesota and Wisconsin for the winter. This winter we are playing host to large visitors from the far north…Snowy Owls. These huge white owls are ‘irrupting’ into southern Canada and the northern United States. The irruption is most extreme in Eastern North America with a report of 150 different Snowy Owls seen in one day in Newfoundland. There was even a Snowy Owl reported in Bermuda.
What is an irruption? It is an irregular movement of a large number of birds, or animals, to an area where they aren’t typically found in such high numbers. Snowy owls and other northern, non-migratory, owls often move southwards to find prey when the food sources in their home range decline. This winter the Snowy Owls that are arriving in Eastern U.S. appear to be well fed and in good health, so they may not be leaving due to low food supplies as reported in this live science article. There have been a few Snowy Owl reports from our area, with one reported south of Hastings on December 28th. If you do go out to look for Snowy Owls, make note of the amount of black barring on the bird. Older owls have less barring than younger birds. Males have less barring then females. A pure white owl should be an older male while a heavily marked Snowy Owl is most likely to be a young female. Observe the owl from a distance and report any Snowy Owl sightings to ebird.org so that scientists can track this magnificent species to learn more about Snowy Owl conservation.
Everyone has heard the derogatory term, “Bird Brain”. What about “The Wise Old Owl”? Are birds’ brains full of nothing but fluff? Or are they wiser than we give them credit for? The truth lies somewhere in between.
Owls, long associated with Athena the Goddess of Wisdom, have the reputation of being wise and all-knowing. It is true that these silent predators perform their ecological roles wonderfully. Tawny Owls are fearless defenders of their nestlings and have caused serious injuries to many who wander too close. Barn Owls can hunt in complete darkness, triangulating the location of their prey with their sound capturing facial disks and off-set ears. Great Horned Owls can carry away prey that weighs as much as they do. However, owls aren’t doing calculus. Their immense eyes can see their prey by the light of one candle. Their enormous mouths can swallow a rat whole. Put the eyes, ears and mouth together and that leaves very little room in an owl’s skull for a brain. Approximately 1/3 or less of the skull’s volume is dedicated to owl brain. Nevertheless, owls have all the intelligence they need to survive.
Psittacines and corvids are at the other end of the brainy bird spectrum. “Alex” the African Grey Parrot learned more than 100 English words that he used appropriately to name and describe objects. Alex could even combine known terms to describe a previously unknown object. Another example of intelligent birds are Crows, Jays, and Ravens. During the past decade many research papers have documented the intelligence of crows through observations of New Caledonian Crows. These birds will use tools, a feat once thought to differentiate intelligent creatures from the less mentally-gifted. Not only do these crows use tools, they have been caught on video, creating tools to solve problems.
What about our backyard birds? Chickadees have tiny brains but this doesn’t mean they aren’t adequately equipped in the cerebral realm. To survive our brutal,snow-covered winters, chickadees collect and store large amounts of seeds. After snow blankets the earth, these tiny passerines must remember where all those seeds are stored. During the fall the portion of a chickadee’s brain that is responsible for remembering these food cache locations actually increases in volume by 30%. The chickadees brains grew new neurons to improve the efficacy of their memory. After the winter the birds’ brains decrease in size, only to expand again the following autumn. Contrary to early beliefs, the growth of new neurons during adulthood isn’t isolated to birds. There is evidence of limited new neuronal growth in the hippocampus, the part of the human brain associated with memory, even in adult humans. Scientists hope to learn more about this process in order to combat brain altering diseases such as Alzheimer’s and Parkinson’s.
“Woolly Bears in the Snow” sounds like the title of a fun children’s book. However, this month CNC received a call about a Woolly Bear caterpillar on the snow. Surprisingly it is not uncommon for CNC naturalists to receive calls in the late winter about caterpillars, cocoons or moths. Most frequently the calls are about giant cocoons that appear suddenly on top of the snow crust in February or March.
Moths and butterflies use a variety of survival tactics when faced with our frigid Midwestern winters. The most well-known is the 3,000 mile Monarch Butterfly fall migration. These *wise* creatures escape before winter turns brutal. But not all moths and butterflies undertake such an arduous journey. Mourning Cloaks prefer to stay right where they are, over-wintering as adults in the shelter of barns or tree holes. Other species of moth and caterpillar overwinter as eggs, pupa (chrysalis/cocoon) or caterpillars.
In the case of the Banded Woolly Bear, the caterpillar spends the winter dormant under the leaf litter beneath an insulating blanket of snow and ice. Dormant is a nice way to say that these tiny insects are equipped to survive freezing. They produce large quantities of glycerol, a cryoprotectant, which keeps their cells from rupturing when they freeze. In the spring the Woolly Bears become active, form a cocoon and metamorphose into the Isabella Tiger Moth (Pyrrharctia Isabella). A relative of our Woolly Bear, the Arctic woolly bear moth (Gynaephora groenlandica), actually has a life cycle that involves repeated freezing and thawing. Due to the harsh conditions in the Arctic Tundra, and the short growing season, it can take up to 14 years for the Arctic Woolly Bear Moth to grow from an egg into a moth. That is the longest life cycle of any moth or butterfly.
And what about those giant mystery cocoons that appear on the snow in the late winter? The cocoons are the over-wintering stage of a giant silk moth species. The most common in the Midwest are the Cecropia, Polyphemus, Promethea Silkworm and Luna Moths. These species only have one generation a year. The caterpillars feed on a variety of plants including trees such as box elder, cherry, birch and oak. In the late fall silk moth caterpillars weave large brown cocoons. The cocoons may be wrapped in group of leaves, attached to a branch or on the ground. In the spring a beautiful moth hatches out, but it will only live a few days. These moths do not even have mouth parts to allow them to feed. Their sole purpose is to mate, lay eggs and start the next generation of silk moths. In the late winter it is not uncommon for these cocoons to be dislodged from branches by the wind and weather
If you find a Woolly Bear caterpillar or a silk moth cocoon in the winter, do not bring it inside. If it warms up during the wrong season there will be nothing for it to eat, or in the case of the silk moth, no other moth to mate with. Odd as it sounds, the best thing for these amazing insects is to leave them out in the cold.
Later this month the Smithsonian Wood Thrush researcher will be returning to the St. Croix River Valley to relocate 25 gps-geotagged thrushes. These tiny Neotropical migrants travel over 3,000 miles twice a year on their spring and fall migrations. Already one geo-locator has been removed from a returning thrush that was captured during a routine banding session at Warner Nature Center. Wood Thrush populations have been declining by about 2% a year since the 60’s. This partnership research project aims to pinpoint where the thrush spend their winters, which will help when developing a species conservation plan.
In similar news, researchers have finally documented the INCREDIBLE journey that the tiny Blackpoll Warbler makes every year. Instead of migrating across land from northern Canada to Venezuela and Columbia, these small birds leave northeastern US and Canada and make a 1,400-1,721 mile non-stop flight across the ocean to arrive exhausted in Puerto Rico, Cuba and the Greater Antilles. And they only weight 12-13 grams. One of the researchers is quoted as saying “There is no longer any doubt that the blackpoll undertakes one of the most audacious migrations of any bird on earth.” To read more about the Blackpoll research visit The Boston Globe.
In late May I found a Wood Thrush dead outside a strip mall window in Hastings. This bird had traveled all the way to Costa Rica, or Mexico, and back, only to break its neck trying to reach the tree reflected in the store window. Neotropical migrants depend on safe winter and summer habitats, as well as critical migratory stop-over points in between. One of those stop-overs could be YOUR backyard. This June, as you clean your windows and fill your bird feeders, take a moment to evaluate your own backyard habitat. Can you plant more native species which can better feed and shelter native insects and animals? Can you modify your windows to keep birds from killing themselves in the reflective glass? Many window suppliers offer windows with screens on outside, such as those by Andersen Windows on Carpenter Nature Center’s Administration Building. For windows that don’t have external screens, the American Bird Conservancy makes window tape. Stop by this summer as we add the tape to more of the non-screened windows. Together we can make a difference for our songbirds.
Have you ever wondered why some plants brag about their flowers by showcasing them at the top of the plant, while others covertly hide the flower under the leaves?
It all comes back to survival and in this case the importance of pollination. Wild Ginger grows along the shady trails in the woodlands at Carpenter Nature Center. During the spring its large leaves spring out the soil, hiding an intricate rusty red flower that sits at the base of the plant on the ground. The flower is bell-shaped and some people say it looks like a jug that has been knocked onto its side. This flower isn’t using UV maps to attract bees. Instead it is trying to attract small flies that emerge from the soil in early spring. These flies are interested in feeding on the thawing carcasses of animals that died during the winter. Although scientists debate whether or not the fly is the primary pollinator, the color of the flower does resemble decomposing animal flesh and the flies are observed entering the flower and getting covered in pollen.
During the summer the Wild Ginger’s seed matures. The seed has an elaiosome. An elaiosome is small oily food gift that is attached to the seed, which entices ants to take the seed and elaiosome underground where it will ultimately germinate and form a new plant. Native Americans and early settlers used the plant as a spice but researchers today believe it contains poisonous compounds. Wild Ginger was also used as a poultice to treat wounds, and modern science has confirmed the presence of two antibiotic compounds in the plant.