Explore the Fascinating Life at the Bottom of Puget Sound

1. Interesting Facts

• The Puget Sound region formed when several microcontinents collided and attached together. Later, glaciers shaped the region further.
• The Puget Sound has a surface area of 1,020 square miles and a shoreline length of 1,332 miles. It also includes more than 200 islands. It would take 18 days to walk the whole shoreline.
• The sound is home to many species, including 3,000 invertebrates and over 200 fish species. Dozens of birds and marine mammals also call the sound home.
• Puget Sound is home to the world’s largest octopus species, the giant Pacific octopus. This species can reach over 150 pounds and have an arm span of up to 20 feet. In the 1960s, the sound used to host the annual World Championship of Underwater Octopus Wrestling, which is exactly what it sounds like.

2. What is Puget Sound?

You’ve probably heard of Puget Sound. However, what exactly this sound is can be complicated.

A sound is a smaller body of water connected to a more immense sea or ocean. It can refer to an inlet broader than a fjord but deeper than a bight. It may also be a narrow sea or ocean channel between two bodies of land. (Who thought there were so many ways to talk about bodies of water?)

What is Puget Sound? (cont.)

Puget Sound is an inlet of the Pacific Ocean and part of the Salish Sea. It is located along the northwestern coast of Washington state, U.S. The marine waterways and basins are interconnected in a complex system. Puget Sound has one primary and two minor connections to the open Pacific Ocean.

What is Puget Sound? (cont.)

Puget Sound stretches about 100 miles from Deception Pass to Olympia. On average, its depth is 450 feet, though its maximum depth is closer to 1000 feet. Puget Sound currently ranks as the second-largest estuary in the United States, following Chesapeake Bay.

3. Why is Puget Sound So Deep?

Puget Sound was formed partially by glacial erosion. In other words, a glacier pushed through the area during the last ice age, cutting through the land. This glacier carved out the coast and then melted after the ice age ended, which left a deep gap in the land. The sea then flooded the basin, leaving us with Puget Sound.

Why is Puget Sound so Deep? (cont.)

Glaciers are huge fortresses of ice that are basically unstoppable. They cut through the land like butter. Therefore, they are able to leave very huge basins.

4. What Lives at the Bottom of Puget Sound?

Puget Sound is a complex ecosystem of life. It’s part of the sea, but also not part of the sea. Therefore, it hosts a wide range of different habitats and life.

You’ll find many sediments on the very bottom of the Puget Sound. These sediments may not look like much, but they provide a habitat for many different animals. (As it turns out, many animals evolved to live in dirt.)

What Lives at the Bottom of Puget Sound? (cont.)

These animals include oysters, octopuses, sea urchins, clams, crabs, and sea stars. The area is known for its high population of Dungeness crabs, which live in the sediment and improve the surrounding water for other species.

What Lives at the Bottom of Puget Sound? (cont.)

Dungeness crabs release nutrients and control pollution. Many animals eat them, making them a key part of the marine food web. Many of these invertebrates also provide a source of income and food for people.

What Lives at the Bottom of Puget Sound? (cont.)

Besides invertebrates, you’ll also find a range of underwater plants at the bottom of Puget Sound. These plants include kelp and eelgrass, for the most part. These underwater plants provide shelter, food, and spawning grounds for various animals. They’re part of the life of most species in the area.

Kelp is a substantial type of seagrass that tends to form thick forests in Puget Sound. These forests can support many animals, including crabs, snails, birds, and sea otters. They are both a source of food and a reliable hiding spot.

What Lives at the Bottom of Puget Sound? (cont.)

Eelgrass is a smaller type of seagrass known for its flowers. They often grow in soft sediments in shallower water, while kelp grows in deeper waters and rockier sediment.

Many fish species use eelgrass as a nursery. It provides a place for smaller fish to hide until they are large enough to venture into open water. Eels also stabilize sediments and prevent erosion.

Rare Animals of Puget Sound: Chinook Salmon

Chinook Salmon are some of the most prized salmon that live in the Pacific. They’re commonly called blackmouth salmon or king salmon (for their size). However, they are endangered in Puget Sound, mainly due to overfishing and habitat loss

Chinook Salmon (cont.)

Since tracking began in 1984, the Salish Sea Chinook population has declined by 60%. However, the population has been stable since 2002, though there has been a decrease in salmon returning to spawn over the last few years.

Of course, fewer salmon breeding means fewer babies. Therefore, the salmon population is expected to drop again soon.

Rare Animals of Puget Sound: Tufted Puffin

The tufted puffin is another species important to the Puget Sound ecosystem but is also quite rare. These colorful seabirds have yellow tufts on their head, which is how they got their name.

Tufted Puffin (cont.)

Tufted puffins are becoming endangered in Puget Sound due to several factors, including human disturbances, oil spills, and reduced food availability. Researchers are concerned that the area may lose the puffin altogether.

Rare Animals of Puget Sound: Sixgill Shark

These large, ancient sharks have (unsurprisingly) six gills. They live in the very deep water of Puget Sound, where they feed on squids, crabs, and fish. These sharks can tolerate a low salt level in their water, allowing them to live in Puget Sound.

They do not prey upon humans, though they do have plenty of teeth. Sixgill sharks live very deep, though, so seeing them is extremely rare.

Rare Animals of Puget Sound: Orca

Orcas are known to swim in every ocean on Earth. Therefore, it’s not surprising that they have ended up in Puget Sound, too.

Three main types of orcas live in Puget Sound: resident, transient, and offshore. While these three types are very similar, they eat different foods, which has led to different behaviors.

Orca (cont.)

Resident orcas consume mostly fish (particularly salmon). They are divided into two groups based on location: southern and northern. The southern group is endangered due to pollution, prey depletion, and noise. There are about 75 individuals left today.

Offshore orcas are rarely seen. They eat primarily sharks and other fish. Transient orcas are much more elusive and feed on mainly marine mammals, like seals. While each type of orca has different behaviors and populations, seeing any of them is pretty rare.

Rare Animals of Puget Sound: Marbled Murrelet

Marbled murrelets are small seabirds that grow brown-marbled feathers during the breeding season. They nest in old-growth forests near marine waters and eat various small fish and invertebrates.

Marbled Murrelets (cont.)

These birds are a bit picky about where they settle, so their populations have declined due to the loss of old forests. Decreases in local fish populations may also affect them.

Studies on the species’ diet are underway, which may help researchers determine if lowering fish populations is affecting them.