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Showing posts from 2015

The Biggest Bird on the Beach

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If you are from the Oregon Coast, you know that bald eagles are seen in great abundance along the shore. But this hasn’t always been the case. In the past, bald eagles had such low population numbers that they were put on the endangered species list. Before 1972, DDT was a popular pesticide that was used all over the country. In coastal areas, the chemicals in this pesticide would end up in the ocean, building up in fish populations that eagles and other large raptors would then prey upon. The chemicals used in DDT would soften eggshells, making bald eagle reproduction success rate very low. Once the use of these chemicals was banned in the United States, eagle numbers began to rise and they were eventually switched from the endangered species to threatened species. It wasn’t until 2007 that eagle numbers were high enough to remove the bird from both endangered species and threatened species lists.  
Nowadays, with such a large abundance of seabirds, like those seen at Haystack Rock, i…

The Rocks are Alive?

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Many of us are intrigued by the large animals seen at Haystack Rock, which unfortunately leaves most people to step over, or even on, hundreds of very delicate creatures that cover almost every visible rock, barnacles!
Barnacles are crustaceans, related to crabs and shrimp. Although we mostly only see them motionless and stuck to rocks, they expend lots of energy to stay alive and live in a variety of places! 
The first stage of a barnacle’s life is a free swimming, one-eyed larva. It hatches from a fertilized egg as a result of sexual reproduction. The barnacles mission at this stage is to find a surface to live on for the rest of its life. This could be attached to a rock, a ship, a whale, a crab, or any other hard surface which will allow the animal to settle.
The method barnacles use to attach themselves to surfaces in a wet environment is rather intriguing. Researchers have recently (2014) discovered that this is a two-step process. The first substance that is secreted onto the…

Life in the Intertidal Zone

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The intertidal zone is the area between the high and low tide lines.  It is an area rich in nutrients and is the home to a variety of inhabitants, but it is a harsh habitat where the inhabitants have to survive in both the sea and on the land.  The Intertidal has four distinct zones. The spray zone is submerged only during very high tides or during storms, but will be 'sprayed' by sea water by splashing waves and wind-blown spray. The high intertidal zone is submerged during the peak of the high tide and is out of the water for long periods between the high tides. The middle intertidal zone is typically exposed during the hours surrounding the low tide and low intertidal zone is exposed only during the lowest tides.

Most human visits to Haystack Rock are during low tide when much of the intertidal zone is exposed and the inhabitants are exposed to the air. While the human visitors leave as the water submerges the landscape with the incoming tide, the inhabitants remain and hav…
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It’s that time again! The full moon is approaching, bringing some of the lowest tides of the year and the tide pools are waiting for explorers!
Exposure at the Needle during a negative low tide Photo Courtesy of Alanna Kieffer
Tides for the approaching week:
Friday, July 31st –low tide: -1.4’ @ 7:18 AM High tide: 6.7’ @ 1:56 PM Low tide: 1.6’ @ 7:20 PM
Saturday, August 1st – low tide: -1.5’ @8:00 AM High tide: 7.1’ @ 2:36 PM Low tide: 1.2’ @ 8:10 PM
Sunday, August 2nd– low tide: -1.4’ @ 8:41 AM High tide: 7.3’ @ 3:16 PM Low tide: 0.8’ @ 8:59 PM
Monday, August 3rd – low tide: -1.1’ @ 9:22 AM
high tide: 7.5’ @ 3:57 PM Low tide: 0.6’ @ 9:50 PM
Tuesday, August 4th – low tide: -0.5’ @ 10:03 AM High tide: 7.6’ @ 4:40 PM Low tide: 0.5’ @ 10:44 PM
Wednesday, August 5th – low tide: 0.1’ @ 10:48 AM High tide: 7.6’ @ 5:26 PM Low tide: 0.5’@ 11:44 PM
Thursday, August 6th – low tide: 0.9 @ 11:38 AM High tide: 7.5’@ 6:17 PM
The best times to see the tide pools at Haystack Rock are during negative low tides!…

An Uncommon Visitor

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Every once in a while we receive a visit from an uncommon inhabitant in the tidepools ... this week it was an octopus! It was a small octopus; note the size relative to the anemone in the following picture.


Octopus in the Tidepool Photo Courtesy of Alanna Kieffer
Octopi have eight arms which typically bear suction cups. The majority of octopi have no internal skeleton or outer shell resulting in an almost completely soft body. The one exception is the beak, made of chitin, similar in shape to a parrot's beak. The soft body allow an octopus to squeeze in and between narrow spaces in rocks where they can hide from predators. They can also eject a thick, blackish ink in a cloud to aid in escaping from prey.
The octopus has a relatively short life, anywhere from 6 months to 5 years for some of the larger species. Reproduction is typically the cause of death; males live only a few moths after mating and females die shortly after their eggs hatch.
Most octopi are subtidal creatures, but…

They Look Like Flowers!

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Sea anemones may look like flowers but that are actually predatory animals. There are over 1000 species found worldwide in coastal waters in various sizes, shapes, and colors. They attach themselves to firm objects, primarily rocks at Haystack, and have a column-like body which is symmetric along the radial axis.  The anemone does not have a skeleton and can flatten or extend its body by changing its internal water pressure.

The Giant Green Anemone (Anthopleura xanthogrammica) is a common find in the tidepools of Haystack Rock. The green color comes from a symbiotic algae that lives in the tissue of the anemone.


Giant Green Anemone in the Tide Pool Photo Courtesy of Jeff Lemelin
The anemones mouth, surrounded by tentacles, is the single body opening. The tentacles have poison stingers, called nematocysts, that are used to catch food. The anemones are carnivores, typically feasting on fish, mussels, small crustaceans, worms and marine larvae. Even though the tentacles have poisonous st…

Nudibranchs in the Tidepools

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Nudibranchs, also referred to as sea slugs, can frequently be spotted in the tidepools at Haystack Rock. There are many species of nudibranch, most having outstanding markings and colors. The nudibranch feed on bryozoans, hydroids and sponges and it's color can be changed by the food it eats.   The nudibranch has a pair of sensory projections on their head, called rhinophores, which allow them to smell and taste. Virtually all nudibranchs have some form of eyes but they are not well developed and in most cases are little more than a pigment spot in the head near the rhinophores.  The nudibranch breathes through gill projections which extract oxygen from the seawater. The Pacific Northwest has more than 200 species of nudibranchs.

The Opalescent Nudibranch (Hermissenda crassicornis) could be called 'showy'. It is found from Alaska to Baja, California and can grow to two inches in size. At Haystack Rock, it can be found in the sandy bottom of a tidepool. It is slender with n…