Firefly Watch 2021

Just because I haven't been writing this year doesn't mean I haven't been doing nothing this whole time. I completed my 4th season of Firefly Watch. This program is run by Massachusetts Audubon, but anyone anywhere can participate. 

Observation protocols are simple. Count how many flashes you see in three separate ten second periods. I space mine ten minutes apart to get varying levels of darkness, starting just before sunset. We also record the flash pattern (single, double, or triple flash for instance), start and end times, wind, precipitation, and temperature. For good measure, I also record the colors of the flashes. I start at the end of May and depending on how long I keep seeing fireflies, I go until late August or early September. I use the same location every year to track the same population, and try to stick to the same dates every year.

2020 saw an increase over the previous year and 2019 saw a slight decrease, with 2018 being the initial and baseline year. 2021 was the first year to see a significant decline in the number of flashes. Not only was it lower than last year's total, it was the lowest of all four years. In 2020 I counted 708 flashes. In 2021 I counted 593, a 16% decrease. 

I have no explanation for the drop. There were a few more rainy nights when I was doing observations in the previous years, and that may have grounded some of the fireflies. One night early in the season there was a thunderstorm with heavy rain and gusty wind and no one was flying that night. But in the previous three years I counted a grand total of 17 flashes on that date. While rain may account for some missing fireflies, it still leaves quite a void. Hopefully 2022 will see a rebound.

Year by year comparison of flash counts

Flashes by date

The Hunt for Red Knot

For the second time in three years, I journeyed to the Delaware Bay beaches of New Jersey in search of the red knot, a long-distance voyager from South America. In 2019 I spent a day scouring Cape May County and while I had a great day of birding, I was unsuccessful. I decided to try again in a year, spending a few weekdays on vacation there to have 24 hour access to the beaches while avoiding the weekend crowds. That trip was cancelled because of Covid, although I'm sure the shorebird migration was unaffected. This year I was able to make the trip, giving myself a Sunday, Monday, and part of Tuesday to find the elusive little sandpiper.

Red knot (USFWS)

Sunday, May 23rd was one of the warmest days of the year so far. I wasn't in a rush to get anywhere so I wasn't on the road at the crack of dawn, but I didn't want to waste any daylight. Leaving by 7:30 was a good compromise. I made great time getting to the beaches in the area of Villas, NJ. Two years ago my first stop was Kimbles Beach, a part of Cape May National Wildlife Refuge. I decided to stop there first again. There were laughing gulls and "peeps", a generic term for the little sandpipers that all look alike to me. They weren't present in as great a number as 2019, and it could be because this year's trip was a little later in the migration than before.

Peeps and gulls feeding at Kimbles Beach

The tide was on its way out, and there were quite a few horseshoe crabs on the beach, and pearly green eggs in the wrack line. Some were making their way back into the bay, while others were burying themselves in the sand. Still more were dead, becoming meals for the birds and other critters. I scanned up and down the beach, but no red knots. There was a volunteer naturalist on duty, and she told me to check back later in the day when the tide is coming back in, about four in the afternoon.

Horseshoe crab eggs

It was late morning, so I had quite a bit of time to kill until then. My next stop was Higbee's Beach, where I saw my first American oystercatcher two years earlier. This time there were more people than birds on the beach so I didn't spend much time there. The highlight of this beach was a whelk egg case that had washed ashore.

Whelk egg case

The clock was still slowly ticking away until the tide returned, so I went to Fire Control Tower #23, a World War II observation tower. It was lovingly restored and opened to the the public for tours while I was living in Washington, and in 2019 I arrived just after it closed for the day. I was determined to get inside this time after years of wondering what was in there.

Skipping over the history lesson and staying on track with nature, the real reason for my visit, I had a picnic lunch at Cape May Point State Park before hitting the trails there. The trail I chose was a loop through a maritime forest and around a freshwater pond. Swans and ducks were beating the heat with a swim, songbirds serenaded me, and the air was scented with saltwater, bayberry, and eastern red cedar. Some wildflowers added a splash of color, and a muskrat lodge was the only sign of mammals. By the lighthouse, a flock of purple martins flitted around their little hotel on a pole, calling to each other and snagging insects like little flying acrobats.

Muskrat lodge

I checked in at my AirBNB just a block from the bay and took a nap until it was time for the tide to return. I went back to Kimbles Beach and waited. The horseshoe crabs were still there, and in greater numbers. The laughing gulls and peeps were still there, but no sign of red knots. A few other people came to the beach and we talked about wildlife for a while. I was scanning to the south and Liz, a birder from North Jersey, was scanning to the north. She spotted the red knots in a mixed flock. Finally, after two years I got the bird I was after. Much like the first time seeing the horseshoe crabs spawning, it was a surreal experience.

Horseshoe crabs coming ashore to spawn

A mixed flock that includes red knots

Seeing the red knot on the first day freed up the rest of my time to look at other wildlife areas. I went to Sunset Beach, hoping to catch a glimpse of Mercury and Venus after sunset, but the clouds had already come in by then. I spent some time at the gift shop and got a few items for my friends while I waited for the traffic situation there to clear out, then got some nighttime lighthouse pictures.

Monday was cloudy, drizzly, and about 30 degrees cooler. I wasn't about to let a few raindrops ruin my day. A rainy day at the beach is better than a sunny day at work. After breakfast in Cape May, I went to the Nature Conservancy's Garrett Family Preserve. It's a small property in between a residential neighborhood and Cape Island Creek. The property is a matrix of forest and field up against a salt marsh. I saw and heard quite a few songbirds, a young rabbit, a baby diamondback terrapin, a duck, a turkey vulture, wildflowers, a pile of feathers and bones, and some bee hives. In the salt marsh, there was an osprey on the nest and a bunch of holes where I saw some kind of motion. It was fiddler crabs scuttling back into the holes when they saw me coming.

Baby diamondback terrapin

My next stop was South Cape May Meadows, another Nature Conservancy property on the Atlantic. I first went there in 2019 and had a great day of bird watching. This time was more of the same, despite the drizzle. I saw my first glossy ibis and more turtles. However, it was just turtle heads poking out of the water so I couldn't tell what kind they were. There was another muskrat lodge, swans, ducks, geese, terns, and peeps. On the beach in the fenced off nesting area there were terns, oystercatchers, and some other bird that was too far for me to identify. I came across a toad, lots of feeding peeps including dowitchers, otter scat, and more piles of feathers where some bird met its demise. 

Long-billed dowitcher

Beach toad

Glossy ibis

A walk around Lake Lily brought me pond lilies, a robin fledgling, and a family of swans. After a late lunch I went to the wildlife refuge's Two Mile Beach unit on the Atlantic outside of Wildwood. While I didn't see them, there are snowy plovers nesting there. By the time I got there, the rain became steadier than a drizzle and the dark clouds and high wind made for an angry looking ocean. I continued walking the trails. More ducks and peeps, my first eastern towhee, and my first yellow warbler were waiting for me.I decided to head back to the bay to see if the red knots would be back with the rising tide. But first, I had to hit the boardwalk and grab some more gifts. Bubble blowing unicorns are in, license plates with your name are out.

Kimbles Beach was getting a steady rain when I arrived, but the wind was gone. Despite the incoming tide, the waves were almost nonexistent. So were the crabs. And so were the red knots. I decided to order dinner and call it a night. I had one last stop planned for Tuesday before going home, but my GPS wanted me to drive around a trailer park so I just left. One of the last things I saw before leaving New Jersey was a great blue heron flying over the Delaware River. 

The plan for finding the red knot worked. I avoided weekend traffic for the most part, I slept in an ideal location, the weather was mostly cooperative, I learned a lot, and saw a blend of new sites and old. I saw close to 30 different bird species, 5 that I never saw before, including the one bird I went to see. My long weekend was a nice break from the office and recharged my batteries for me, in spite of the miles I put on my feet.

The 17 Year Itch

That sound you hear isn’t the Six Million Dollar Man using his bionic powers. It’s cicadas by the billions. Every year, at least a few cicadas emerge during late spring and serenade us with their mating call. Chunky and scary looking, these insects are totally harmless but to me at least, just hearing them makes it feel a little hotter and muggier. 

This year is a little louder than most. Brood X, the largest brood of periodical cicadas, is emerging after 17 years underground in the larval stage. They’ve been tapping into tree roots during that time and now that they’ve reached adulthood they’re ready to go out in a blaze of noisy glory. They'll mate soon, lay their eggs in the tree tops, and die. When the eggs hatch, the larval cicadas will drop from the tree, burrow into the ground, and start the timer on another 17 years.

Expect it to be a little louder than usual in the Northeast
(From "This Is Spinal Tap")

All those bugs means not just a lot of noise, but also a lot of food for just about everything. The reason cicadas emerge by the billions is to overwhelm their predators’ stomachs. The strategy is that lots of cicadas will get eaten, but based on sheer numbers, many will survive to continue the life cycle for another 17 years. 

Periodical cicada (NPS)

Speaking of 17 years, why such an odd number? It’s another evolutionary strategy. What other critter can you think of with a 17 year life cycle? It reduces the risk of broods emerging during a population boom for a predator species. As a double failsafe, broods have stragglers that emerge either before or after the 17 year period.  Most are within a 13 to 21 year period. It gives the brood a better chance of survival in the event that the 17th year is a boom year for predators. 

Molting cicada (Baltimore Sun)

I've never seen a cicada coming out of its shell. Like all insects, they have a hard exoskelton, and immediately after emerging they molt. From what I'm being told, people all over are finding a lot of those shells on tree trunks and other surfaces. I haven't seen any yet this year, but I haven't been able to get outside much other than a birding expedition to New Jersey which you can read about later. This week's information comes from the University of Connecticut. 

Weird and Wonderful Water

Water is the stuff of life. We can't live without it, and neither can the rest of the food chain. The search for extraterrestrial life hinges on whether or not a planet or moon contains liquid water, but that assumes that any life off Earth is the same as Earth-based life. This week we'll take a look about what makes water so special and how it keeps all of us alive.

Water, the most abundant substance on Earth.
Unless air is more abundant.

Water is unique among all chemicals (yes, it's a chemical) because it is the only one found in solid, liquid, and gas states naturally on Earth. While ice and water vapor aren't basic requirements for life, they are key components of the water cycle. Water stored as snow and ice in the mountains is slowly released during the dry summers in the American west, meaning a steady flow in rivers throughout the year. Clouds made of water vapor transport precipitation over long distances. On top of that, ice and steam make modern life more convenient- think food storage and electricity generation.

Winter snow waiting for the spring melt, March 2016

Typically, solids are more dense than liquids, which in turn are more dense than gases. Water flips this around, as ice is less dense than liquid water. If you freeze a container of water, you'll notice that the ice fills more of the container than the water did. This is why your frozen pipes burst in winter. The expansion of water as it freezes is a visual of the density decreasing. Because ice is less dense than water, it floats. Because ice floats, it forms on the surface of lakes and other bodies. This allows aquatic life to survive. If water froze from the bottom up, everything would either freeze in place, or eventually be exposed on the surface.

Molecular structure of liquid water and ice (Mountain Empire CC)

Water has adhesive and cohesive properties. Water molecules stick to each other (cohesion) and other substances (adhesion). Adhesion causes capillary action. This is the movement that is responsible for plants being able to absorb water in the ground through their roots, up the stem, and to the highest leaves. Cohesion also contributes to surface tension. Water molecules on the surface are more tightly packed and can resist pressure from outside forces. This allows objects to float. Water striders can stand on the surface because of surface tension.

Water strider striding water (National Wildlife Federation)

Water has a high specific heat. Specific heat is the amount of energy needed to raise the temperature of a gram of water by one degree Celsius. Because it takes a lot of energy (1 calorie per gram) to heat water, it takes a lot of heat to boil water. Ocean life appreciates not being boiled. Water also holds onto heat it absorbs and releases it slowly, moderating Earth's temperature and making the seasonal changes gradual.

Water dissolves more substances than any other. The polar structure of the water molecule. The positive hydrogen end will attract negative ions, while the negative oxygen ends attract positive ions. Water's solvency is important for plants and animals to absorb nutrients, and for animals to flush waste from their bodies. Nonpolar substances like fats do not dissolve. That's where the saying "Oil and water don't mix" comes from. Less dense fats will float on top of water, and with some skill they can be separated.

Next time you take a drink, raise a glass in appreciation of water. Without it, your drink wouldn't be here and neither would you. This week's information comes from USGS and Mountain Empire Community College.

Species of the Month

Halloween is just around the corner. Traditionally, we examine a spooky critter with a connection to Halloween for the Species of the Month. This year let’s try something different. There’s nothing scary about a ghost crab, but its name fits the season. 

Ghost crab (Science Magazine)

Scientific name: Ocypode quadrata 

Kingdom: Animalia (animals)

Class: Malacostraca (soft-shelled crustaceans)

Order: Decapoda (ten-footed crustaceans)

Range: Rhode Island to Brazil 

Habitat: Ocean or estuary beaches, from the tide line to the dunes 

Lifespan: 3 years 

Diet: Bean clams, mole crabs, sea turtle eggs and hatchlings, organic detritus 

Predators: Shore birds, gulls, raccoons 

Conservation status: No special protection

Other info: Ghost crabs are small, nocturnal crustaceans. They grow to about a two inch carapace (back shell) with long legs and eye stalks, and their claws are uneven sizes. Ghost crabs hatch from an egg in the ocean and go through six larval stages before developing into adult crabs. Unlike other crabs that can only mate when the female is molting, ghost crabs can and do mate at anytime after reaching maturity which is usually after a year old.  

Juvenile ghost crab (NPS)

Ghost crabs live in burrows in the sand. They plug the holes during the day and emerge at night for feeding and mating. Mating occurs near the male’s burrow. They travel several feet per night and may not return to the same burrow. Occasionally they will go into the water to wet their gills; they are also capable of absorbing water from the sand into their gills. 

Ghost crabs can be used as an indicator species to monitor the health of their habitat. Populations can be easily estimated by counting burrows. Knowing the status of the crab population can tell what kind of impact human activities are having on the ecosystem overall. Off road vehicles and coastal development are the biggest challenges we give them. 

A pair of ghost crabs (NPS)

Once again this week's information comes from the Animal Diversity Web at University of Michigan. Next week is a rerun. We'll have fresh content after Halloween. Stay tuned!