Firefly Watch 2019 Results

Beginning in late May and concluding in September, I conducted observations for Massachusetts Audubon again this year. I count how many flashes I see in three separate periods of ten seconds each. I usually separate those periods by five to ten minutes, to allow for increasing level of darkness. Mass Audubon asks for data other than how many flashes. They also want time and date, weather conditions (cloud cover, precipitation, wind, and temperature), flashing patterns (single flash, double, triple, J-shaped), and color of flashes. Weather may affect firefly behavior, while color and pattern indicate separate species of fireflies.
After two years of submitting observations for my location (my parents' back yard), I don't have enough data to notice any population trends yet. To track population trends, I tried my best to conduct observations on the same dates as last year. This wasn't always possible, like the night I had to chose between fireflies and my daughter's graduation. Guess who won.

Graph of 2018 firefly flashes

Comparing 2018 to 2019, there was a slight decrease in number of flashes but not statistically significant. The first fireflies were seen the same day both years, while the last was seen about a month later in 2018 than in 2019. Peak flashing began almost two weeks earlier in 2019 than in 2018, and following crash was much sharper, without the brief rises that occurred in 2018. My guess is that with a earlier and longer peak, mating was successful and there was no need to keep looking for a date.

Graph of 2019 firefly flashes

What I was told by my mom before I began this project in 2018 was that there weren't really any fireflies around anymore. Since then, I've learned it's not true. She says there are definitely more now, but without any data to back it up I have to take her word for it. I don't remember if there are more or less than when I was a kid. It's not something I was looking at scientifically at the time. I do remember seeing fireflies in September only once before 2018 though. I don't remember what year it was, but I remember they didn't show up until late June, so we had them for the same length of time that I was used to.

Graph showing 2018 and 2019 flashes

Since the end of the season, I moved a few miles away. Despite having to drive a little farther, I will continue observations at my parents' house for consistency. It's hard to establish a trend if I don't use the same location. I may add my new location and start a data set here as well. After getting a second set of data, I am closer to being able to track populations. I am already looking forward to the return of next year's fireflies and the data they'll give me.

Be Bear Aware

With the arrival of fall and the approach of winter, food sources are becoming scarce for some animals. Bears spend the winter either hibernating or in torpor, a state of lowered metabolic and other bodily activities. To prepare, they begin gorging themselves this time of year so they can have enough calories to last through an extended period of not eating. While they generally try to avoid humans, now and when they emerge in spring (very hungry) are the most likely times you will encounter a bear. Here are some helpful tips on how to avoid or survive a bear encounter.

Don't let this happen to you! (US Forest Service)

Hungry bears are attracted to food and will follow their noses. When camping, store food, drinks, utensils, cookware, dishes, cosmetics, and hygiene products in a bearproof container, locked in a vehicle, or suspended 10-15 feet above ground and 4 feet on all sides from a climbable surface. Sleep in a tent or camper away from your cooking area. Don't sleep in clothes you cooked in. Don't set up camp near berry patches, carcasses, and bear signs. Avoid foods with a strong smell like bacon and fish, no matter how good they are. Sleep near your flashlight and bear spray. If you see a bear try scaring it away by making loud noises. If it is undeterred, move away to a safe area.

Ideal camp setup (WildAware Utah)

When hiking, if you see a bear that hasn't noticed you, move away quickly, quietly, and calmly. Never try to run from a bear. Running might trigger the chase instinct and the bear will always beat you in a race. If you see a bear and it notices you, let it know that you are human and  not food or another bear. Talk to it calmly, move your arms about, and keep an eye on it without making eye contact. Hopefully the bear will leave. If it does, walk away in a different direction. If it remains, back away slowly but keep making small talk. If the bear approaches you and is acting defensively- making loud noises moving its head around, or stomping or pawing at the ground, stand your ground. If the bear approaches, it's probably bluffing. Keep talking calmly to it, and start backing away when it stops coming at you. If it comes at you again, stop moving but keep talking until it stops again. If it attacks you, now is the time to play dead. Face down on the ground, keep your backpack on if you have one. If the bear rolls you over, keep rolling until you are face down again. Otherwise, don't move and don't make any sound until you're sure the bear is gone.
If you are faced with a quiet bear that won't leave, you'll probably have to fight the bear or at least make it think you want to. If backing away doesn't keep the bear from you and it is behaving calmly, act aggressively to let the bear know that you are not an easy meal. Yell at the bear, make yourself appear as large as possible, throw things at it, swing a large stick at it, and make eye contact. The idea is to make the bear think that since you are crazy enough to fight a bear, it probably shouldn't be messing with you. If the bear decides to attack anyway, fight back with a focus on its face. If you have bear spray, use in situations where the bear is aggressively approaching you. Make sure you are not spraying into the wind, and don't spray it on yourself as a repellent. Read the instructions.
The reason I chose bear safety this week is because I just had my first bear encounter while camping in Virginia. I was tent camping about 30 miles south of Washington, DC and while I got up to use the bathroom at 1 AM a bear took advantage of my absence and ransacked my campsite. It put some holes in my tent, knocked my cooler off the picnic table, and tipped over my folding chair. What did I do wrong? I had my alarm set for 5:30 AM so I could catch an early train into the city. To move more quickly, I had my next day's clothes and my toiletries in the tent with me. That was my first mistake. My second mistake was leaving the cooler in the open. I had 8 bottles of water and 3 glass bottles of root beer in there. I decided the ice would last longer in the woods than it would in the car when drove into civilization, where it's generally hotter. My third mistake, which wasn't really a mistake but just the circumstances, was not having safety in numbers. Bears don't like people; we have a bad reputation in the animal world. Being off-season in the middle of the week, the campground was pretty much empty. With no people around, maybe the bear felt like the campground was OK to stroll through, and the only tent around was an easy target.

Holes in the tent were on the right side, so I'm guessing
the bear moved right to left, swatting the chair over for
dramatic effect.

When I came back to the campsite, the bear was gone. The tent was a heap, so I spent the rest of the night in the car with the doors locked. Yes, I've seen a news article where a bear gets in a car and steals it.  After sunrise, I inspected the damage. There were holes in the tent, nothing too big but they'll only grow each time the tent is set up. None of the drinks were opened and the glass bottles didn't break. Despite their superhuman strength, bears still need you to open a bottle for them. The chair was fine, but I have no idea why the bear decided to flip it. With a damaged tent, I ended my trip a day early. This week's bear safety tips come from the Grizzly and Wolf Discovery Center right outside fabulous Yellowstone National Park.

Crickets

Fall has almost fallen. It's hard to believe summer was in full swing when you last read a fresh Nature Minute blog. Internet issues and life in general kept me from my regular schedule. Maybe where you are, the leaves are starting to turn, there's a bit of crispness in the air, mornings are full of fog, and nights are longer and full of chirping crickets.

Black field cricket Gryllus assimilis (Texas A&M) 

Here in Pennsylvania, crickets typically begin their nightly serenades in the late summer, continuing through the fall. Only the males chirp. They do so by rubbing their wings together, as a mating call for the females. They are most active at night, and even during daytime are hard to find. If they notice you getting close, they'll stop chirping so you really need to look hard if you want to find the source of the chirp. Warmer temperatures will produce more chirps, and the number of chirps drops with the temperature. I never counted chirps before, so I never noticed this.

Northern mole cricket Neocurtilla hexadactyla
(University of Florida)

Many people consider crickets to be a pest because the chirping gets annoying, but they are generally harmless. Since crickets favor loose soil, they are frequently found in flower beds, which are usually right under your bedroom window, giving you a front row seat. At the bottom of the food chain, in large numbers they have the potential to attract other unwanted guests to your home such as raccoons and spiders.

Carolina ground cricket Eunemobius carolinus
(Oklahoma Panhandle State University)

Nature Minute will return in October with more autumnal awesomeness. I'm taking a much-needed vacation. Until then, relax to the sound of the crickets. Don't let them drive you nuts. They'll only be around a few more weeks, and then it will be too cold to keep the windows open at night. This week's cricket facts come from Terro.

Sound of the Wild

Think about the sounds you typically hear over the course of a  normal day. It starts with the alarm clock and quickly fills with noise. The toaster, the hairdryer, the microwave, cars, cars, and more cars, people talking and shouting, buses, trucks, trains, planes, and of course your phone. If you're lucky you heard some birds singing on the way out the door. Other than the lawnmower, popcorn, and a log on the fire, my favorite sounds come from a land far from modern conveniences.
Next time you are out and about pay attention to what you hear. Insects buzzing, birds singing and calling, the wind in the trees (or your ears). In the mountains you might hear pikas and marmots barking, or larger animals like coyotes or wolves howling in the distance. In the fall, you might be treated to the eerie sound of bugling elk.

A not-so-distant coyote, not howling

Water is life, and it also provides a great soundtrack. I can listen to crashing ocean waves or a gurgling river all day long. Rain falling on surfaces other than pavement is a wonderful experience. The pattering on a tree canopy is soothing enough to forget about being soaked, and rain falling in a pond is a magical sound. In a naturally quiet environment like a cave, there's a good chance you'll hear only a single drop of water at a time, maybe a few seconds apart, maybe a few minutes. Even better than rain is the sound of thunder in the distance. This can be a bit worrisome if you're a long way from shelter.

The soothing sounds of the Firehole River

Late summer nights, if there is no thunder, fall asleep to the sound of the crickets. In the spring, fall asleep to the sound of the tree frogs. Another special spring sound, which I've only heard once, is the knocking sound the trees make after the thaw when they start absorbing water and their sap is flowing again. It took a while to figure that one out.

Pacific tree frogs, a sure sign of spring

Here is a link to a short video of some sounds recorded at Yellowstone National Park. Note that the pictures don't necessarily correspond to the sounds. See how many sounds you can figure out!

Species of the Month

Shark Week is nigh upon us and we're getting in on it with July's Species of the Month. I've chosen the most famous (or infamous) sea creature, the great white shark. While they've been known to attack people, we are not their prey. Shark attacks may be curiosity or just a case of mistaken identity. Unlike Jaws, these apex predators won't eat you, even if they do happen to bite. Sink your teeth into this quick profile!

Scientific name: Carcharodon carcharias

Great white shark (NOAA)

Kingdom: Animalia (animals)

Class: Chondrichthyes (rays and sharks)
Order: Lamniformes (mackerel sharks) 

Range: Coastal ocean areas of Asia, Australia, Oceana, North and South America, Africa, and Europe

(NOAA)

Habitat: Marine
Lifespan: 30 to 40 years
Diet: Fish, seals, sea lions, sea birds, squid, sea turtles, dolphins, whale carcasses, rays
Predators: Humans, killer whales, other sharks
Conservation Status: IUCN consideres great whites to be vulnerable, protected in the US

(NOAA)

Other information: This massive apex predator can grow to lengths of 20 feet and weigh as much as 6600 pounds! It's mouth can open to over three feet wide, plenty of room for anything it wants to eat. And that mouth is packed with razor sharp teeth. Unlike humans, gifted with two sets of teeth, the great white can apparently grow an unlimited number, replacing teeth as needed. The shark's streamlined body is built for speed and power. Not much is known about their reproductive habits. Females give birth to live young, which eat unfertilized eggs and possibly even siblings in the womb. They are mostly solitary creatures, but sometimes congregate to feed, such as at a whale carcass. In situations like this, they form social hierarchies. In addition to a well-developed sense of smell, great whites can detect electrical fields. These highly developed sense allow them to detect prey by a single drop of blood in 100 liters of water, or by the beating of its heart. The great white's prefer hunting method is to strike from below. A powerful blow is enough to stun the prey, avoiding a chase or a struggle. Across the board, fish populations are declining at an alarming rate and the great white is no exception. Sport fishing, commercial fishing bycatch, and finning take a toll, and as a large species reproductive rates are generally low. As an apex predator, populations are already low to begin with. Sadly, despite its deadly reputation the great white shark has more to fear from us than we from it.
This month's information comes from the University of Michigan's Animal Diversity Web.
nm1 https://swfsc.noaa.gov/textblock.aspx?ParentMenuId=123&id=21434
nm2 https://sos.noaa.gov/datasets/marine-migration-great-white-shark-3d/
nm3 https://oceanexplorer.noaa.gov/explorations/18whitesharkcafe/welcome.html