Sunday, September 20, 2015

The Biggest Bird on the Beach

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, it’d be surprising if eagles weren’t spotted along the Oregon Coast.  Bald Eagles are a rather large predator, which prey on fish, birds and rodents. Due to their size, they do not have many predators other than those that invade their nests and snack on their eggs. This may include raccoons and other rodents and birds.

Some birds may harass eagles when the eagle is going after individuals of their species. At Haystack Rock, Western Gulls are normally seen pestering the eagles on the hunt. In Cannon Beach, there is an eagle nest in a patch of trees directly across the beach from Haystack Rock. There is also a pair on the north end of Cannon Beach, which prey on the abundance of birds seen on the rocks at Chapman Point. When the eagle arrives at these rocks, it is no secret. There are some very distinct sights and sounds that warn all about the eagles’ presence.
Juvenile Eagle holding Common Murre being pestered by Gulls
Photo Courtesy of Alanna Kieffer 

Juvenile Bald Eagle with Common Murre in talons being chased off by a Western Gull
Photo Courtesy of Alanna Kieffer

Gulls use a loud warning call to signal all the other gulls on the rock to be ready for the predator. Common Murres will abandon their spot on the rock to head out to the water where they are more protected. Cormorants will mostly stay seated; the eagles don’t normally mess with them due to their large and strong beaks. Puffins hide in their burrows and western gulls join the fight. Some dive bomb the eagle while others hover around trying to distract or confuse the eagle. With a wingspan of about 6 feet, it is easy to spot the eagle in the mass of birds.

Bald Eagle posted at Chapman Point
Photo Courtesy of Alanna Kieffer

At Haystack Rock the most common bird seen taken by the bald eagles are Common Murres. Just about every year around the beginning of summer the eagles mate and have a chick. When the chick first hatches, the adults are heavy on the hunt for food to feed their chick.  Once the chick is old enough to hunt, the juvenile will head over and learn the ways of hunting at the rock.

Eagle after an unsuccessful hunt at the rocks
Photo Courtesy of Alanna Kieffer
Bald eagles can be seen at Haystack Rock all year round, but the beginning of summer is a prime time to see some eagle action! Like most nature, you may never know exactly when the eagle is going to strike but the gulls will definitely let you know. Next time you’re at the rock and the birds start to get noisy, remember to look for the Oregon Coasts largest bird of prey, the bald eagle!

Wednesday, August 26, 2015

The Rocks are Alive?

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 surface is a lipid, displacing water from the chosen area. The next step is to secrete an adhesive compound in order to stick to the now water-free surface. When the barnacle finally attaches itself; it attaches its head to the surface it has chosen to stick to.

The next stage of the barnacles’ life involves a lot of feeding. For barnacles seen in intertidal zones, such as those seen at Haystack Rock, they will be seen in two different ways. Mostly, they are seen as motionless creatures. This is because when visiting the tide pools, the water is low and the barnacles are not submerged. This results in the barnacles closing in order to keep hydrated while the tide is out. They are then overlooked and damaged. Sometimes, if close enough to a large rock, people can hear a clicking sound coming from the rock; this is the barnacle circulating the water it has held inside. When visiting the tide pools many people jump around from rock to rock. While it may seem like a harmless little step, with so much exposure time and so many visitors during this exposure, these animals go through a tremendous amount of mortality.

If looked for closely, many barnacles can be found underwater feeding! To do this, barnacles use their feather-like foot to grab phytoplankton out of the water. There are two types of barnacles found at Haystack Rock, acorn barnacles and gooseneck barnacles. 

Acorn barnacles are the most common and don’t look like much more than a jagged rock.

Acorn Barnacles attached to California Mussels. 
Photo courtesy of Alanna Kieffer
Giant live acorn barnacle during negative low tide at Haystack
Photo courtesy of Alanna Kieffer

Gooseneck barnacles are a bit more noticeable than acorn barnacles due to their appearance. Most of the time gooseneck barnacles will be found along the top of the high tide zone and in very large clumps. Gooseneck barnacles get their name from having a long neck which is the part attached to the rock. The most visible part of the barnacle is on the end of the neck and is the part that tends to resemble a crustacean. This is the plated calcium shell. 
Piles of Gooseneck Barnacles in a crevice at Haystack Rock
Photo courtesy of Alanna Kieffer

When seen submerged in the water, as in the picture below, the calcium shell will open and the feather-like foot will come out and the barnacle will begin feeding. Macro and microscopic plankton, tiny organisms that cannot swim against the oceans current, will get trapped in this barnacles foot.

Feeding gooseneck barnacles
Photo courtesy of Alanna Kieffer 
Treat everything you ever encounter as a living animal until you find out otherwise, this will prevent any accidental and unnecessary damage. Remember that just because something is not constantly moving doesn't mean it is not a living creature. 

Go explore some tide pools with your new knowledge and see how many feeding barnacles you can find in one pool!

Thursday, August 6, 2015

Life in the Intertidal Zone

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 have must survive under the water.

Haystack Rock at Low Tide
Intertidal Zone exposed to the air
Photo courtesy of Carolyn Propst

Haystack Rock at High Tide
Intertidal zone covered by water
Photo Courtesy of Carolyn Propst

The inhabitants of the intertidal zone have to adapt to huge daily changes. At high tides the inhabitants are covered with salt water but are exposed to the air at low tide, so they must be able to survive in both. When submerged, the inhabitants are subjected to the turbulence of the water that can dislodge or sweep them away so they will burrow into the sand, attach to rocks, or live under rocks. While submerged, the temperature remains relatively constant but, when exposed, the air temperature can range from below freezing to extreme heat. Tidepools that form during low tides can have a salinity near that of the sea or much lower when rainwater or runoff dilutes it and the inhabitants have to adapt. The inhabitants also have a variety of predators - when submerged by the tide they are preyed upon by sea animals and when exposed birds and marine mammals will prey on them.

There are many inhabitants of the intertidal zone that thrive at Haystack Rock and can be spotted near low tide.

Sea Stars and Anemones
Photo Courtesy of Carolyn Propst

Photo Courtesy of Carolyn Propst

Mussels and Anemones
Photo Courtesy of Carolyn Propst

Photo Courtesy of Carolyn Propst

The Haystack Rock Awareness Program is committed to educating visitors about the inhabitants of Haystack Rock and conveying the importance of protecting them while they are exposed at low tide. HRAP Interpreters are on the beach every day at low tide and are happy to answer any questions you have about the inhabitants of the Intertidal zone!

Thursday, July 30, 2015

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 1stlow 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 3rdlow tide: -1.1’ @ 9:22 AM
                                    high tide: 7.5’ @ 3:57 PM
                                    Low tide: 0.6’ @ 9:50 PM

Tuesday, August 4thlow tide: -0.5’ @ 10:03 AM
                                    High tide: 7.6’ @ 4:40 PM
                                    Low tide: 0.5’ @ 10:44 PM

Wednesday, August 5thlow 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! This is the time when the tide pools are most exposed and there is the most to see. Most negative low tides are super early in the morning, so grab your coffee and your water shoes and get down to the beach! There are also low tides in the evening but these are not as low as the morning tides and therefore will not have as much exposure.

The West Coast of the United States experiences what are known as mixed semidiurnal tides. Semidiurnal means that there are two high and two low tides everyday. The word mixed represents that the two low tides as well as the two high tides in one 24-hour period are different heights, with one low-low tide and one high-low tide everyday.

Waning Moon on July 28, 2015 
Photo Courtesy of Alanna Kieffer 

The level of the tide is mostly affected by the moon, sun, and Earth’s position around each other. With a new or full moon approaching, the Earth, sun and moon are all aligning with each other. The gravitational pull of the moon combined with that of Earth is what to blame for pulling the water up and down our shores. With the full moon on the August 1st, the tides will be at the lowest point on this day at 8:00 AM. When the moon is not full, it is approaching the sun at an angle and the two gravitational pulls cancel each other out, therefore the tides are not as extreme.

Exposure at the Needle 
Photo Courtesy of Alanna Kieffer

So come to the tide pools as soon as possible to catch the lowest of the low tides! If you can’t make it out this week there will also be some negative tides again towards the middle and the end of the month. Plan your trip accordingly to land in the pools at the right time. Always remember no matter how low the tide is, most animals still need space, so do not disturb the birds and please use tide pool etiquette when exploring!

Happy tide-pooling!

Thursday, July 23, 2015

An Uncommon Visitor

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 smaller species will inhabit tidepools, typically near caves and smaller openings is rocks. An octopus is an uncommon visitor to Haystack Rock so it was a real treat to have one spotted in the tidepools last weekend.

Octopus in the Tidepool
Photo Courtesy of Alanna Kieffer

We hope to see you in the near future on the beach. Perhaps you will spot an uncommon visitor to the tidepools! HRAP Interpreters are on the beach daily at low tide and can answer your questions about the inhabitants of the tidepool.

Wednesday, July 8, 2015

They Look Like Flowers!

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 stingers, they only feel a little sticky if you touch them since the skin is too thick to allow penetration of the poison. While the anemones eat a variety of animals, they have very few predators.

The Moonglow Anemone (Anthopleura artemisia) is also found at Haystack Rock. The tentacles have distinctive white bands that often have a luminous quality which is where the species gets its name 'moonglow'. This anemone is usually found in sandy areas where it is attached to a rock.

Moonglow Anemone in a sandy tidepool

Anemones can reproduce sexually or asexually. During asexual reproduction, called lateral fission, an identical animal sprouts from the side of the parent anemone, growing until it can survive on its own. In sexual reproduction, the anemones release eggs and sperm into the water which produces free-swimming larvae.

Sexual Reproduction - Moonglow Anemone

Right - Sexually reproducing Moonglow Anemone
Left - Bleached Aggregating Anemone

There are lots of anemones at Haystack Rock - take a closer look at them the next time you visit the tidepools! Interpreters are on the beach during daily low tides and can answer your questions about anemones and the other inhabitants of Haystack Rock!

See you on the beach.

Tuesday, June 16, 2015

Nudibranchs in the Tidepools

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 numerous gills (called cerata) that are orange with white tips. There is typically an orange area of the back that is bordered in blue, although the colors may vary.

Opalescent Nudibranch 

Opalescent Nudibranch with aggregating anemone

The Rufus Tipped Nudibranch (Acanthodoris nanaimoensis), on the other hand, is not nearly as showy as the Opalescent. This nudibranch has a white or gray body that is covered with projections with yellow tips, except for the gills which have red tips. It lives in the low intertidal zone and typically grows to just over 1 inch long.

Rufus Tipped Nudibranch

 Other Recent Sightings at Haystack Rock

Pile Worm (Nereis vexillosa)

Ochre Sea Stars (Pisaster ochraceus)

Purple Shore Crab (Hemigrapsus nudus)

This weekend will be eventful one on the sands of Cannon Beach; the 51st Sandcastle Contest is Saturday, June 20th. On your way to the sand creations, make sure to make a stop at Haystack Rock and discover the inhabitants of the tidepools for yourself! HRAP Interpreters are on the beach every day at low tide and are happy to point out the tidepool dwellers and answer your questions!