Sea Whip

Domain: Eukarya
Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Gorgonacae
Family: Gorgoniidae
Genus: Leptogorgia
Species: Leptogorgia virgulata

I’ve realized that so far the only corals I have mentioned have been hard corals—reef builders. I will admit, that I like more hard corals than soft, but that doesn’t mean soft corals aren’t worth talking about. Continuing with my Chesapeake Bay theme, I’m going to talk about a native soft coral, the Sea Whip.

Cue the 80s music: “Crack that whip!” “Just whip it!”

The major difference between hard and soft corals is the composition of their bodies. Hard corals have permanent, rigid exoskeletons that house the coral polyps. These structures require large amounts of energy to build, which is why it can take a year for hard corals to grow just an inch, at best. Soft corals, however, lack that rigid calcium carbonate skeleton. Instead, soft corals are mostly made of living tissue that allows the soft corals to assume more creative shapes.

Sea whips, Leptogorgia virgulata, have long, thin branches that can grow up to a meter long. Their coloring can vary from red, to tan or orange, to purple. The polyps are always white, so sea whips look like they’re covered in white fuzz. Most soft corals are more colorful than their harder cousins.

Sea whips are found in reef environments and can tolerate low levels of salinity, so they are most common in nearshore areas that are more influenced by the tide. They range from New York to the Chesapeake Bay and from Florida to Brazil. In the Chesapeake Bay they thrive in the salty waters of the lower section of the bay.

L. virgulata are suspension feeders, so the polyps use their long tentacles to snag plankton and other tiny particles that are suspended in the water. When sea whips are born, the tiny polyps are carried by waves and currents. When they reach adulthood, so to speak, they become sessile meaning they cannot move from the hard substrate they land on. So they rely heavily on water circulation to stir up the water and bring in more plankton and nutrients for them to feed on.

I have yet to see a sea whip while diving, which is something I wish to change. But I wanted to share this soft coral to show that not all corals are found in tropical places, and that corals can be a lot more diverse than we think. And I’m happy to report that as of this writing, the populations of sea whips in the Chesapeake Bay and other monitored areas are considered stable!

Sources and more info:
https://www.chesapeakebay.net/discover/field-guide/entry/whip_coral
http://www.dnr.sc.gov/marine/sertc/octocoral%20guide/Leptogorgia_virgulata.htm
https://naturalhistory2.si.edu/smsfp/IRLSpec/Leptog_virgul.htm

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Alexandrium monilatum

Domain: Eukarya
Kingdom: Prostita
Phylum: Dinophyta
Class: Dinophyceae
Order: Gonyaulacales
Genus: Alexandrium
Species: monilatum

After spending some time talking about the horrors of invasive species, let me throw you a curve ball. We should all agree that invasive/nonnative species are harmful to us and the environments that they infiltrate. However, not all native species are good for their environment either.

How can organisms that are part of the natural balance of their environment be bad for it?

The simplest explanation I can give is this example. Our bodies need potassium to function properly, which we get from food like bananas. If our bodies don’t have enough potassium, then our muscles cramp and we can become stiff and sore. If we consume too much potassium, then it can poison and even kill us. Don’t worry, though; you would have to consume a truck load of bananas in a single day for that to happen.

Like our own bodies, environments need everything in moderation.

Alexandrium monilatum is a single-celled dinoflagellate found in the warm waters of the Atlantic Ocean, Gulf of Mexico, Caribbean Sea, parts of the Pacific Ocean, and the Chesapeake Bay. It is a special kind of bioluminescent algae; when agitated, the organism produces its own light in the form of a soft blue glow.

This dinoflagellate can reproduce sexually and asexually, meaning it can use its own genetic material to make copies of itself without the use of other individuals. It can also produce chains of individuals, ranging from 2 to 80 A. monilatum per strand.

A. monilatum uses photosynthesis to create its own food, making it a phototroph. It is preyed upon by small fish and filter feeders, making it part of the base of the food chain. So how can this armored alga be a bad thing? It sounds so productive, and it even glows blue at night when waves stirs the water!

The problem with A. monilatum is that it is considered a Harmful Algal Bloom (HAB) species. When conditions are right, this species will reproduce faster than it can be consumed by its predators, causing an algal bloom in the water. Blooms are large patches of algae that are seen by the naked eye, meaning there are millions of individuals concentrated in a single area.

Blooms are considered a problem because the water contains a finite amount of nutrients available to the algae. Once the supply runs out, it’ll take time to replace those needed nutrients. So these blooms are extremely productive for a short time, before the algae run out of food and die. When they die, they start to decompose. The process of decomposition takes up a lot of oxygen, and without the photosynthesizers there to replace the oxygen being used, the water becomes hypoxic—or worse, anoxic.

Once the amount of dissolved oxygen in the water is depleted, the area becomes a dead zone, and all the fish and other marine organisms either leave or suffocate in the water. Dead zones aren’t always permanent; however, they are still an inconvenience to the marine life and to us and should be prevented at all cost.

It is not my purpose to make Alexandrium monilatum out to be a bad guy, just to show that even native species can harm their environment under certain conditions. Algal blooms, or red tides, can be caused by a steep increase in important nutrients found in fertilizers, which enter the water as run-off from nearby farms, gardens, and agricultural facilities. A boom in available food causes a boom in creatures that depend on it, and that’s true no matter the species.

Bioluminescent algae are fascinating. I was lucky enough to swim at night in a lake full of a species of bioluminescent algae, though I’m uncertain what species it was. It was a magical experience that I will never forget, so I was excited to talk about A. monilatum and to discuss the importance of balance within an ecosystem.

Sources and more info:
https://naturalhistory2.si.edu/smsfp/IRLSpec/Alexan_monila.htm
https://www.chesapeakebay.net/discover/field-guide/entry/alexandrium_monilatum
https://www.vims.edu/bayinfo/habs/guide/alexandrium.php
https://www.vdh.virginia.gov/environmental-epidemiology/harmful-algal-blooms-habs/alexandrium-monilatum-hab-in-lower-york-lower-james-rivers-and-chesapeake-bay/frequently-asked-questions-faqs-alexandrium-monilatum/

Humpback Whale

Humpback whale jumping out of the water. Photo taken from pexels.com

Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Balaenopteridae
Genus: Megatera
Species: Megatera novaeangliae

When we speak, hum, sing, etc. we make those noises by vibrating our vocal cords. Sometimes, when you hum or hold a note, you can even feel the vocal cords in your throat. Whales can also sing. In fact, male humpback whales sing to communicate and can be heard for miles by other whales, each “song” lasting up to about 30 minutes.

Fun fact: scientists don’t know how humpbacks pull off singing, because they have no vocal cord.

Humpback whales get their common name from the way they arch their back when diving. They aren’t the largest or heaviest whales in the world, but they do have the longest flippers. Their fluke and wing-like flippers can help you identify the whale as a Megatera novaeangliae, and the unique white splash-like markings on those appendages allow scientists to distinguish between individuals, like a fingerprint.

These creatures can be found in all of the world’s oceans, in both tropical and polar regions, though they don’t venture too far up into the poles.

M. novaeangliae are a type of baleen whale, meaning that they don’t have teeth like we do, and they take in large amounts of water that, hopefully, contain a lot of krill and small fish. Humpback whales are different from other baleens because they can actually trap their prey through a process that is better to watch in a video or documentary (e.g. Blue Planet).

When humpbacks find swarms of krill or schools of small fish, they will try to gather them together. They do this by exhaling air while they spiral around their prey. This action creates a “bubble-netting” that confuses and traps the prey, allowing humpbacks to dive below and lunge upward to feed upon their prey. Like I said, I highly recommend watching this on a video or a documentary because it’s incredible to see, and if you get a chance to see it in person, all the better!

I feel like humpback whales are underappreciated. I first learned about them when I started watching nature documentaries in high school, but it wasn’t until college that they started getting more fleshed out in my mind.

They’re amazing creatures that produce eerily beautiful songs. I should know; I had to listen to some in a lab class in college, and they have a unique feeding behavior for baleen whales. While they’re not endangered or threatened, their populations have been reduced to a fifth of what it once was due to whaling practices—that’s mind-blowing to me!

If what you’ve read has piqued your interest, please take the time to learn more about these creatures. There’s so much that I couldn’t add, and who knows, maybe your curiosity will lead you into a job that will allow you to understand the mysteries of their singing.

Videos of bubble netting:

Sources and more reading:
Ocean: The Definitive Visual Guide made by American Museum of Natural History
Ocean: A Visual Encyclopedia made by the Smithsonian
Marine Mammals Evolutionary Biology 3rd edition by Annalisa Berta, James L. Sumich, and Kit M. Kovacs
https://animaldiversity.org/accounts/Megaptera_novaeangliae/
https://www.chesapeakebay.net/discover/field-guide/entry/humpback_whale
https://oceanwide-expeditions.com/to-do/wildlife/humpback-whale
https://www.nationalgeographic.com/animals/mammals/h/humpback-whale/
http://wildwhales.org/speciesid/whales/humpback-whale/
https://www.fisheries.noaa.gov/species/humpback-whale
https://us.whales.org/whales-dolphins/species-guide/humpback-whale/

Chesapeake Bay, United States

So far, I have talked about places that I want to see for myself in the future, and I’ve yet to talk about anything that is a bit closer to home for me. It’s not that I don’t like the places closer to home, but I think sometimes I forget that what is normal for me may considered extraordinary to other people. Today, we will be talking about the Chesapeake Bay, which plays a role in my life every day.

The Chesapeake Bay is the largest estuary in the United States and is the third largest in the world. A quick-and-dirty definition of an estuary is it’s an aquatic area in which rivers meet the sea, where freshwater and saltwater mix.

Now, the Chesapeake Bay is fed by over 150 rivers and streams, but its main source comes from the Susquehanna River. The total area of the bay is about 3200 square miles. For those that need help visualizing how big the bay is, it’s about three times as large as Rhode Island, and it is also bigger than the state of Delaware—that’s a lot of area! And it’s not just water; this even covers all the various salt marshes and sub-estuaries around it as well.

Surrounding the bay are coastlines that belong to both Maryland and Eastern Virginia, but the watershed that it belongs to includes four other states! Even though the productivity of the bay has decreased drastically over the years, it still provides more fish and shellfish than any other estuary in the United States and provides over 500 million pounds of seafood a year, so if you like eating oysters or crabs, they probably came from the Chesapeake Bay.

The bay is very important because it supports more than 3600 plant and animal species; it also supports more than 17 million people who live, work, and play in and around the bay. If you’ve never visited the area, I highly recommend spending time somewhere along the bay. There are many beautiful camp grounds you can stay at. There are boating and fishing opportunities, and all sorts of trails and parks around the bay that will give you a beautiful scenic, and informative look at the life of an estuary and its salt marshes.

There are even places where you can sign up to help clean up the trash and pollution from surrounding areas that get washed up. It’ll definitely take more than a single trip to see even half of what there is to offer, but visiting the Chesapeake Bay will be totally worth it in the end—especially if you have great weather to experience it in!

The Chesapeake Bay is very important to me because I have always been one of those 17 million people that it has helped to support. I have been to camp grounds around the bay and have sailed it a few times. It is a beautiful place to lose and find yourself, and I believe it is an environment worth saving and preserving for many generations to come!

So, please, if you have the time, come and see this place for yourself; it truly is a national treasure! And who knows, you may see dolphins or a humpback whale or two.

Sources and cool links:
Ocean: The Definitive Visual Guide made by the American Museum of Natural History
https://www.cbf.org/about-the-bay/chesapeake-bay-watershed-geography-and-facts.html
https://www.nps.gov/chba/learn/nature/national-treasure.htm