Today the world celebrates Earth Day - a day to celebrate the place we all call home.
What will you be doing to help the Earth today? Whether it's packing your lunch in reusable containers, using less plastic, cleaning up a local roadway - all those actions can add up for the benefit of the oceans and marine life.
Leave a comment below and let me know how you are celebrating Earth Day!
Barrier Reef Image courtesy NASA
Can you identify this species? I took this image yesterday off of Cape Cod, Massachusetts.
Jennifer Kennedy, Blue Ocean Society for Marine Conservation
Last Monday's Mystery Creature image featured two gray seals. Unlike some other seals, who have a rounded, dog-like head, gray seals have more of a horse-like snout. Their scientific name Halichoerus grypus references another terrestrial farm animal - it translates to "hook-nosed pig of the sea."
Gray seals are fairly large seals. Males can reach lengths up to 10 feet and weights up to 880 pounds, while females grow to about 7.5 feet and 550 pounds. They live in cold water in the Atlantic Ocean and Baltic Sea.
Gray seal populations have expanded in many areas, prompting a debate about culling the animals. But they do face threats - natural predators include sharks and orcas, and they can get entangled in fishing gear.
The term pinniped refers to the group of about 27 species of seals, sea lions and walruses. The term pinniped is Latin for wing- or fin-footed, and refers to the flippers that all pinnipeds possess, which makes them adept swimmers.
There are 3 types of pinnipeds:
- Otariidae (eared seals and sea lions) - animals with a visible ear flap on each side of their head
- Phocidae (earless, sometimes called "true" seals) - animals that have ears, but they don't have a visible ear flap
- Odobenidae (walrus) - one species of walrus
This week's Mystery Creature is a species of pinniped - do you know which one?
Image: Steller Sea Lions, Courtesy David B. Ledig/USFWS
I've added some new content this month, much of which I've blogged about today! But here's a list in case you want to check out these new articles:
- Horseshoe Crab Profile
- Northern Quahog Profile
- Parrotfishes Profile
- Stoplight Parrotfish Profile
- Midnight Parrotfish Profile
- Bioerosion Definition and Examples
- Gills Definition and Examples
Is there something related to marine life that you'd like to hear more about? Leave your suggestion in the comments!
You've probably heard the term erosion, which is when waves, wind or ice can carry pieces of earth or rocks away. But have you heard of bioerosion? Bioerosion, used in reference to marine life, is when marine organisms such as invertebrates, fish or even algae break off pieces of rocks or coral.
One example of bioerosion is feeding by parrotfish (I've been a little obsessed with parrotfish after seeing some beautiful ones in the Florida Keys this winter!). The midnight parrotfish, for example, feeds on algae housed within coral. When the midnight parrotfish feeds, it uses its beaklike jaw to bite off pieces of coral, then crunches them up with additional teeth in its throat. The fish eats the algae, while the crushed coral gets excreted as waste (search for parrotfish online and you'll probably see lots of references about parrotfish pooping sand, and this is why).
A lot of times, erosion isn't a good thing. Think of your favorite beach getting washed away, bit by bit, as sea level rises. Not so much fun. But in the case of parrotfish and corals, bioerosion is a good thing. Breaking up the coral results in two things: small pieces of coral that can form new reefs, and ground-up coral falling to the ocean bottom in the parrotfish's waste, which recycles the nutrients necessary for reef-building.
Learn more about bioerosion and see other examples here.
Image: Midnight parrotfish, Courtesy Tam Warner Minton, TravelsWithTam.com
Last week's Mystery Creature was a type of clam called the northern quahog, or hard-shelled clam. Northern quahogs are a clam with a large, thick shell. They are found buried in mud or sand in waters from the Gulf of St. Lawrence to Florida and Texas.
These clams are filter-feeders. They have an inhalant siphon that extends to the surface of the sand and draws in water. The water is drawn through the gills, where sheets of mucous pick up small organic particles and algae, which are then passed to the mouth. The leftover water is expelled via another siphon. This filtering allows the clam to get food, and also filters the surrounding waters. So we want to keep clam populations healthy, because the filtering of clams improves water quality.
Quahogs are an important food source, and are referred to by size. Little clams (up to about 1.5 inches) are called littlenecks, medium-sized clams (about 2 inches) are called cherrystones, and larger clams are called quahogs or chowders. The pronunciation of the word can differ, but usually sounds something like "co-hog" or "qwa-hog."
Image: Northern Quahog, Courtesy NOAA Photo Library, Flickr
What is it? Leave your answer in the comments below!
Image Courtesy Silke Baron, Flickr