Above: Photo of Male monarch on Spotted Joe- pye weed. Copyright 2013 Pamm Cooper
Most people who are butterfly aficionados have noticed that the Monarchs are few and far between this year. I have only seen two all year, and I am always out and about on power lines, in meadows, and walking trails where there is plenty of milkweed for the caterpillars to eat and native nectar source plants for the adults. The second monarch butterfly I saw was just this weekend at the Hebron Fair. It was all over the Spotted Joe- Pye weed outside the Better Living building. Hopefully, we will begin to see more as they begin their journey to Mexico where they spend the winter.
Any butterflies that emerge in late summer and early fall in the Northeastern United States will migrate to Angangueo, Mexico, where they rest hanging on Oyamel fir trees. As long as there is not a period of wet followed by a freeze, the monarchs are able to survive even a snowstorm, as long as snow is not prolonged. The monarchs that survive the winter will leave their overwintering site and travel back up to the Eastern U.S., laying eggs on milkweed as they go. As these early caterpillars hatch and complete their lifecycle, they will also begin travelling north, laying eggs until milkweed sources run out. Monarch butterflies from this second generation are the ones that will migrate to Mexico, having never been there before.
When there is a hard winter that is followed by a hard spring/ summer, Monarchs may have a difficult time surviving the journey northward. That is what happened in the winter of 2012- 2013 and the spring and summer this year. The spring was cold and dry in the southern portion of their migration, and flowers for nectar and milkweed for larvae were not as abundant as usual. June here in New England was unseasonably cold and wet and may have slowed monarchs on their way up here.
According to “ Monarch Butterfly News ‘, the number of butterflies that migrated to Mexico to overwinter in 2012 was 80% less than normal- 60 million vs. 350 million. The reason was attributed to low reproduction due to excessive heat and drought during the summer of 2012. So far this year, numbers of both caterpillars and butterflies in New England seem to be very low. It may take a few favorable years to return populations to previous numbers.
Some people that have butterfly gardens containing milkweed wonder why they never find a chrysalis on the plant even though there was a caterpillar on it. Many caterpillars, including the monarch, leave the host plant and may travel quite a distance before climbing up a plant to pupate. The monarch below I found on a giant foxtail on a rainy September day. The butterfly is resting right beside the chrysalis shell from which it has just eclosed. This butterfly would have begun its journey to Mexico after muscling up on some nectar.
As a final note, sometimes people get worried when they see milkweed tussock moth caterpillars on the same milkweed plant as a monarch caterpillar. They think they will be fighting it out for the same food, when in fact, the tussock prefers the older bottom leaves and the monarch the upper, newer, green leaves. So one minor “ problem “ solved!
Above: Milkweed Tussock Moth caterpillar.
Above: Monarch caterpillar ready to pupate. Both Photos copyright 2013 Pamm CooperPhoto copyright 2013 Pamm Cooper
Pamm Cooper
Uconnladybug's Blog 
September 10, 2013 at 5:54 pm
I know where all the monarchs are this year….. In my yard! I’m very shocked to hear that others noticed a decline in the number of monarchs because for me this year’s numbers were more than I ever remember seeing. I’m directly in the center part of the state. I have deck off the back of my house and have butterfly bushes of various colors planted all around my deck. Butterfly bushes are great because not only do they attract all types of butterflies, insects and other pollinators, but they stay in bloom for months. In addition I have red bee balm planted at the base of the bushes which can be seen from quite a distance away and 100 feet away I have herb fennel (not to be confused with bulbing fennel) growing in my garden. Herb fennel is the favorite plant for Monarchs to lay eggs on. I planted it specifically for the butterflies and it was much appreciated!
Each time I sit out on the deck it’s like a symphony of monarchs; they are everywhere! I have some really nice photos that I could share if interested. During the peak, the bushes would be covered with Monarchs as well as several other species of butterflies and moths. There are also several hummingbirds and multiple hummingbird moths (which are awesome!) plus lots and lots of bumble bees and honey bees and a variety of flying pollinating insects. It was nice to see both a praying mantis and a walking stick on one of the bushes.
I don’t know about a shortage of monarchs in general, but the butterfly friendly plants and bushes I have planted made sure there was no shortage in my back yard ☺
Lisa L. Central CT.
September 10, 2013 at 6:42 pm
I have contacts with many people who are either managing naturalized landscapes and nature centers, have nectar source gardens as you do, or are hikers or bikers who are frequently in the middle of natural settings where monarchs have been commonly seen in past years. This year the observations of these people have been the same- few if any monarch butterflies or caterpillars have been discovered until just recently- late August through the present. Most of these are migrating south now, and perhaps you are fortunate to be on a migration route, as I used to be when I lived in New York State. I am interested to know if you have any milkweed planted as well as nectar source plants, as without it, the species cannot continue to produce viable progeny. Have you seen any monarch caterpillars in your garden, or is it strictly geared toward attracting adults?
September 12, 2013 at 12:42 pm
I have a nontoxic garden center where I usually see HUNDREDS of Monarchs in a season. This year, as usual, we have plenty of moths, swallowtail butterflies,honeybees, bumblebees, lacewings, wasps and other pollinators. I have seen a few Viceroy butterflies (commonly mistaken as Monarchs) but just ONE Monarch butterfly and ZERO Monarch caterpillars this year.