November Monarchs

    Our field season runs from September 1 to October 31, and in some years we see very few monarchs after about October 20.  Big numbers of migrating monarchs arrive to the winter colony sites right around the beginning of November.  Since those colonies are 2000 miles away from Cape May, it makes sense that most monarchs should have passed through this area weeks earlier.  Early last week we saw a few days with cold, windy, and rainy weather, with reports of freezing temperatures and snow from northern New Jersey right up through all of New England.  Monarchs don't survive prolonged freezes, so we figured the migration was over.  For the last several years we have continued to conduct our census into November as a test.  We decided to do that again this year, but when there were no monarchs to be seen during the cold weather -- for a couple of days the census counts were all zero -- we figured our season was truly finished.

Monarch on lantana in Cape May Point, 11/6/20

    Then the weather changed, and suddenly we came into a spell of warm, sunny days.  And monarchs were back!  At first it was just a few, but numbers quickly grew.  It's nothing like the big numbers of early October, but it's still a surprise.  Our seasonal naturalists finished their work at the end of October, but we still have volunteers in town, and collectively we have tagged more than 200 monarchs over the last three days.

Monarch tagged at Cape May Point 11/8/20

    Unfortunately there's not a lot of nectar available for these late monarchs.  We're seeing virtually all of them in the few gardens that still have flowers in bloom -- Mexican sunflower, zinnia, lantata, and Vitex are still blooming in several gardens.  There's also a bit of the seaside goldenrod in bloom out on the upper beach.  But most places have no flowers left.  Many of the monarchs being tagged have little or no fat reserves, and fat provides the fuel for migration.  Will they find enough food to tank up for the next part of their journeys?  Will they find enough nectar as they go south from here to sustain them on their long travels?  Can they avoid freezing temperatures and make it all the way to Mexico?  We really don't know, and we assume that the odds are against the November monarchs, but we continue to actively tag, in hopes that some will be found further south and will provide hints, at least, to the answers to these questions.  We will be astounded (and delighted) if one of these November monarchs makes it to Mexico and the tag is seen by one of the observers there.

    We're also curious about where these November monarchs have come from.  Some that we are seeing are worn or even tattered, suggesting they've been around since before the early November storms, and they might not be fit enough to even try to migrate away from Cape May.  We are also seeing some that are pristine, looking very fresh.  We know that there are late caterpillars each year, and we suspect that as long as the weather permits, there will be newly emerged monarchs entering the population.  We know that they can't have come from terribly far north of here, for the freezes of early November in much of the northeast would have been fatal to any remaining monarchs, whether they were still caterpillars or if they had metamorphosed into the chrysalis or adult stages.  So it's our guess that our November monarchs began their lives in southern New Jersey or southeastern Pennsylvania.

    As long as the monarchs are still here, we will continue to conduct our censuses and we will keep tagging some of the monarchs that are in Cape May Point.  When we are tagging, we often attract curious onlookers, which gives us the chance for an impromptu lesson into monarch biology and conservation.  If you're in Cape May Point while our warm November weather continues, and if you see one of us out there with a butterfly net, don't hesitate to ask about our work, we're always eager to talk about monarchs.

Project Director Mark Garland gives an impromptu lesson about monarchs, 11/8/20

    A reminder: if you see a tagged monarch, make an effort to read the 4-letter, 3-number code on the tag -- the easiest way to do this is often to take a digital photo and then enlarge it on a computer until you can read the code.  Then go online to the website printed on the tag, mwtag.org, and add the requested data.  Watch the monarchwatch.org website in the coming months, for once all the data is assembled they'll report on all tagged monarchs that are subsequently found and reported.

Releasing a newly tagged monarch, 11/8/20

    We have started to compile the season's tagging data, but our annual summary will have to wait until we are truly finished with tagging for the year.  Rain is expected to come later this week, but it's predicted to stay relatively warm, so perhaps we'll keep seeing (and tagging) monarchs for another week or more. When we finally finish, we'll report back on the total number tagged by our team in 2020.

Results of 2020 Census

Monarch nectaring on seaside goldenrod, Cape May Point

    Perhaps the most important parts of the Cape May Monarch Monitoring Project is the census that we conduct.  Our census is modification of a technique known as a "Pollard Transect," whereby a specified route is traveled on a regular basis and butterflies counted by the observer while traveling.  Our census is conducted daily from September 1 to October 31, and consists of a slow drive along a 5-mile route that leads from the west end of New England Road to Alexander Avenue in Cape May Point.  One observer drives at roughly 20 miles per hour and counts all of the monarchs observed along the route.  The census is conduct three times a day from September 1 to October 15, and then twice a day from October 16 to 31.  The number of monarchs seen along the route and the time of travel are recorded and then calculated to monarchs observed per hour.  These data are used to compare one year to another.  This census has been faithfully conducted every year since 1992, giving us 29 years of data.  Our data are summarized on a weekly and annual basis in this chart: 

    So how did 2020 compare to other years?  It was a good year of migration, with the 13th highest yearly average of monarchs observed per hour, 62.4, slightly above the median.  Putting it another way, 12 years have had a higher average but 16 have had lower.  There are many variables that affect the census numbers from year to year, but two seem to be most significant.  One is rather obvious: when the monarch population is high, we can expect to see more monarchs in Cape May.  The other significant variable is weather, with wind direction being the most significant.  A westerly component to the winds is likely to cause many monarchs to drift eastward, and if they end up on the east side of Delaware Bay, their preference to stay over land as long as possible will funnel them into Cape May.  Conversely, when the wind is blowing from the east, many monarchs coming from the north are likely to end up on the west side of Delaware Bay, bypassing Cape May altogether.  The same situation has been observed and is well documented with migratory birds, which are seen in the greatest numbers during the southbound migration when winds are from the west or northwest.  We saw favorable winds more frequently this fall than in many recent years.

Small roost of monarchs at Cape May Pt. State Park, Oct. 5, 2020

    Large average monarchs/hour totals for weeks 6 and 7 correspond to a 2-week period during the first half of October when monarchs were plentiful around Cape May.  It's quite unusual for Cape May to have consistently high numbers for two solid weeks, usually our peak numbers occur for just a few days at a time, though often we will see several peaks during the two-month migratory period.  Even though travel is severely limited this year due to the COVID-19 pandemic, and our education program was severely curtailed as we insisted on compliance with all pandemic precautions, we were able to help many local residents see and appreciate monarch migration during this period, and many more enjoyed the abundance vicariously through our social media posts.

Monarchs roosting in ivy at Cape May Point, October 11, 2020

    When you look at our 29 years of census data, it's noteworthy that while the numbers have some dramatic fluctuations (our highest yearly total is more than 40 times higher than our lowest year), the overall trend seems generally stable.  Some biologists have looked at our data and argued that it indicates that monarch populations are in good shape.  We are very reluctant to jump to that conclusion. Monarchs funneled through Cape May are a very small percentage of the numbers found all across the continent.  Censuses at the wintering areas in Mexico show dramatic declines in monarch numbers.  If monarchs in Cape May are doing okay for some reason, it certainly doesn't imply that monarchs everywhere are equally well.

End of Field Season

The 2020 Field Season for the Monarch Monitoring Project wrapped up on Saturday, October 31 -- our field season runs from Sept. 1 to Oct. 31 each year.  We have started to compile the data and will report back to our followers in a few days, but we'll take a few minutes now to reflect on the season.  The COVID-19 pandemic has impacted virtually everything in all of our lives for most of the year, and that was true for our project as well.  Well into the summer it wasn't clear if we could run the project at all, or if we could hire seasonal naturalists.  Fortunately we found ways to take all of the appropriate precautions and continue to gather data and to hire two naturalists for our two-month season.  Thanks to the generosity of James & Teresa Knipper, who made an apartment available to us, we were able to hire one naturalist from out of the region.  And in the second bit of good fortune, we found a great candidate for the second position living right here in Cape May County.  We introduced them both to our readers before the season began, and now we want to thank them for a job well done.

Jack McDonough

Jack McDonough is a remarkable young naturalist who seems to be genuinely in love with every aspect of natural history here in his home county.  He grew up exploring the Belleplain State Forest of northern Cape May County, and while he is still a teenager, he has an astounding knowledge of our area's plants and animals.  He brought that enthusiasm for natural history to work every day, and while we had many fewer opportunities than most years to engage in educational outreach, Jack still managed to educate and excite the people he would meet while working around Cape May Point.  He's also a very skilled photographer, and he is assembling a set of photos for the use of those involved with the project in future years.  Watch for an upcoming book on the natural history and ecology of Cape May County that he's working on.

Kat Culbertson

Katherine "Kat" Culbertson wouldn't have been available to work with our project had 2020 been a normal year.  She was working as a Peace Corps volunteer in Madagascar when the COVID-19 pandemic forced the Peace Corps to bring everyone back home -- she had been scheduled to keep working over there until 2021.  With plans to begin graduate school in the fall of 2021, she was suddenly left with a gap in her plans, and to our good fortune she found our project and accepted the job on short notice.  Her strong academic background from Harvard University put her in a great position to work with some of the data that we have gathered over the project's 30 year history -- and it looks like a scientific publication will result from her work.  Kat, like Jack, was a great ambassador for monarchs in our educational programs and the many informal contacts that happen when you walk around Cape May Point with a butterfly net.

Our project would not be able to continue without the hard work of our seasonal naturalists.  We offer a huge amount of thanks (and a few very modest paychecks) to both Jack and Kat for the great work that they both accomplished.  We also benefit from the work of many volunteers who help with our tagging, and most importantly, from donors who make contributions throughout the year, whether "adopting" one of our tagged monarchs, contributing to our "Monarchists" team in the annual World Series of Birding fundraiser, or making other donations.  We run a vigorous program on a very small budget -- the salaries of our seasonal naturalists are the biggest expense -- and this year we missed out on the funds that are generated annually as part of our tagging demos at Cape May Point State Park.  Very big thanks to all of you who have made contributions in the past, and if you're in a position to make a contribution this year, contact us at monarchs@njaudubon.org for details on how you can help.

Monarch feeding on Mexican sunflower in Cape May Point

As for the monarchs, we continued to see a few around Cape May Point right through October 31, but with freezing temperatures throughout New England and south into central New Jersey on October 30, we can't expect more to be migrating from our north.  It didn't freeze here, however, and a few late migrants might still be around, but the 2020 monarch season is essentially over.  That's how it should be, as the beginning of November typically heralds the arrival of huge numbers into the Monarch sanctuaries of central Mexico, and indeed people have been seeing thousands upon thousands flying into those amazing Mexican mountain forests.  As we've done for the last 3 years we'll continue our census for one extra week into November, but our job is now mostly wrapping up the season's data, preparing our annual report, and getting all of our project equipment organized and stowed away, awaiting the beginning of the 2021 field season.