Important Information for Beach Goers

Teachers and other visitors:

Download and print or save these 'Tips for your Trip' prior to your beach visit.

To learn more about life in the intertidal zone:

  • Crabs
  • Care of Crabs
  • Newborns
  • Don't Rock the Rocks
  • Moulting
  • Dungeness Crabs
  • Redrock Crabs
  • Field Trip Overload
  • Midshipman

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    Photo: C PrenticePhoto: J. Alford

     

    Crabs

    Every kid loves to turn over the rocks and chase the shore crabs. It’s instinctual with prey of that size and speed and harmlessness- like a game of cat and mouse. Johnny has a great day at the beach and compares how many crabs he caught with Melvin on the bus home. Without realizing it, while enjoying the day on this beautiful swathe of intertidal ocean, their visit harmed or killed many crabs and other beach creatures.

    The problem is that crabs die in buckets without plenty of water. They have gills- they breathe water. Between March and June crabs are also moulting and breeding making them very vulnerable.
    Every year they are innocently decimated over only 5 weeks when thousands of kids visit the Beecher Place section of Crescent Beach.

    Beach Hero at the beach

     Photo: A. Prentice

     

     

     

    Photo: J. Alford

    Care of Crabs

    It is easy to care well for crabs and other beach creatures. Here are some tips on how to make your trip enjoyable for your students.

    Crabs breathe water with gills. Even with water in your bucket, a crab will only last for 20 minutes before it begins to suffocate and die. Crabs need to be returned to their home, where they were found after about 20 minutes.

     

     


    Watch this video to learn about shore crabs and how to care for them in pails.

     

     

    A Beach Hero Interpreter shows kids crabs in buckets of water.
    Photo: M. Cuthbert

    Remember:

    • Collect no more than six crabs per bucket
    • They need about one inch of water per crab to breathe for 20 minutes
    • They also begin to fight when over crowded and trapped in the scary exposed container

    Crabs need one inch of water to breathe for 20 minutes.

    Photo: J. Alford

    Return them to their home after 20 minutes. Just pour the water gently close to the ground.

    Crabs need to be returned to their home, where they were found, after about 20 minutes.

    People carry them out onto the sand where they are picked off by birds.

    Or if they are released on the backshore in dry rocks, they can’t get back to a moist hole before they drown in air.

     

    No bigger than a Twoonie

    • Crabs that are larger than the size of a Twoonie are not shore or hermit crabs.
    • They are most often juvenile Dungeness or Red rock crabs which are legally protected.
    • It is against wildlife regulations to remove protected crabs from the ocean for more than the few minutes it takes to size and sex them.

    This is a juvenile Dungeness crab. It is protected by wildlife regulations and it is illegal to put them in buckets or carry them around if they are not big enough to be legal size and male.
    Other crabs that live in the eelgrass are the kelp and hairy helmet crabs-they are not good eating so are not formally protected, but they are a key species the vitally important eelgrass meadow exposed at low tides.

     

    If the crab is buried in sand, leave it alone:
    breathes water which is in the sand
    may also be soft as moulting
    may be one of the more fragile long-legged kelp crabs. Birds can rip off their legs much easier than on a Dungeness.

     
       
     

    Newborns

    Millions of tiny and microscopic larvae of every fish, crab, clam, etc marine species are floating around Boundary Bay in the spring. Great shelter is found under rocks for them since the current is enough to dislodge them. When those rocks are tipped over or rocked, those tiny baby creatures are killed along with the previous generations lucky enough to land on that rock. The eelgrass in deeper water provides the same shelter for creatures that can cling to it.

    Coincidentally and unfortunately, this is the most fragile time for crabs and marine babies of every species, just born in the last month. They are clinging to the rocks on the shoreline, lucky to get that foothold. The larvae have to avoid open water. They are food for the grey whale still seen feeding in Boundary Bay until yesterday. Food for yearling salmon hitting the ocean for the first time.

    This is a baby seastar just a few months old.
    Photo: J. Alford

     

    Eggs of course are eaten too! Very few beach parents stick around to protect their eggs, but one MALE fish does. Midshipman, a very unusual species of fish, has 2 kinds of males! The parental male is big and guards the eggs. The smaller “sneaker male” just sneaks in to fertilize the eggs!

     

     
    Frilled (aka dog) whelks lay eggs in thick tufts that may be white to pink in colour.

    These baby seastars will be crushed to death if this rock is tipped over or rolled.
    Photo: J. Alford

    		 We ask very visitor to the beach to please, learn, follow and pass along this rule: "Lift, don't rock the rocks" and replace them when you are done just as you found them.

    Don’t Rock the Rocks:

    Don’t tip the rocks, but lift them straight up and out. Crabs and softer or newborn animals may be crushed as the rock is twisted and tipped. So definitely don’t roll over rocks that are heavier than you can easily lift. When you have looked for a few moments, replace the rock exactly as you found it with the water side down and fitting the original spot like a puzzle piece.

    Watch this video to see how it's done!

     

     

    A rock is the roof of the home of tiny fish, shore crabs, periwinkles, and hundreds more smaller species. The house is usually full of water. These creatures dry out and die quickly when exposed up to the air and sun. The roof rock also needs to be put back water-side down in it's original position. For example, limpets travel around the bottom of one rock all their lives. The algae they eat grows back so they just go around again

    Leave cling-ons clinging

    Seastars, limpets, mussels and other creatures survive waves and predators by clinging to rocks and wharf pilings. If picked off a rock or perch, cling-ons rarely survive.

    And why can't we take the beautiful shell home?

    The shell, rock, whatever is someone's house too! Even if we can't see barnacles, or anything moving, something lives there. Tiny and microscopic shrimp, eggs and larvae all cling to ocean debris.

    This shore crab and periwinkle live inside a moulted Dungeness crab shell.

    Barnacles are tiny, the size of your fingertips, and look and feel like part of the rock. They are sharp and a good reason to wear thick shoes with sides.

    Rusty spots on rocks aren't rust; they are eggs masses, lichens and sponges. Crescent Beach used to be known for its carnellian red agates, a stone used in jewelry. Now very few are found because they were collected for decades.

    Moulting

    		  
    Did you know that many of the “dead” crabs that wash up on the beaches aren’t dead at all? They are moulted shells like a snake’s shed skin. Crabs climb out the back of their shells-even pulling out their eyes- when they need more space to grow. They puff out their soft new shell like an over-sized shirt. They need to hide, and be left alone, when they are soft. Crabs dig themselves down into the sand when they moult.

    Their gills are attached to their shell, so they have to leave them behind with the moulted shell. Fortunately, they grow fast because that's how crabs breathe!
    Photo: J. Alford

    Crabs of every size moult. This is a juvenile dungeness.

    If they are soft, leave them alone.

    Most crabs moult in the spring and again in the year as needed by their growth.
       

    Dungeness Crabs

    		  
    Dungeness crabs are identified by the sharp points at the end of the scalloped edge of their shells. They must be measured across the widest section from sharp point to the other sharp point. This crab shell has barnacles attached to it. Microscopic barnacle larvae float in the water and then fall down to the bottom, attaching to whatever is below them.
     

    This crab was being carried in hand by a teenager chasing another teenager on a local beach. It is undersized and once measured, this person gave it up. The crab is gasping for breath and suffocating out of the water. I am poking it to show how crabs defend themselves with their front pinchers. These pinchers, on a crab, larger than 2 or 3 inches, are strong enough to break a finger. This crab was then returned to the ocean immediately.
       

    Red Rock Crabs

    		  
    The red rock crab may range in colour from orange to purple. It is differentiated from the Dungeness crab by the smooth scalloped edge of its shell. It does not have the points on the shell of the Dungeness. Red Rock Crab
       

    Field Trip Overload

    		  

    On Thurs June 10, 2010 on Crescent Beach there were 7 school buses, 3 marked Abbotsford, 2 unseen by me, 1 Surrey. At 25 kids per bus that’s 175 kids hitting the beach at exactly 9:30 am. Add to that the class group I was guiding on a conservation minded walk and field study plus at least 3 others adds another 100 = 275 kids daily. This happens annually from the end of May to the end of the school year. From Wed to Fri over 5 weeks, I estimate 3000 kids visit the Beecher Place section of Crescent Beach.


    Photo: J. Alford


    Carolyn Prentice, coordinator of the Beach Hero program 2010 saw a similar load at a remote and relatively pristine location in South Surrey (and I’m not telling you where) with buses from Abbotsford and Langley. There is no parking for cars let alone buses, so we were shocked to find 300 kids down there on a single day.

    Photo: J. Alford

    We take classes and groups out through our Educational and Beach Heroes programs. Unfortunately, we can only reach a fraction of those thousands of field trippers.
    Because these beaches are not parks, they receive no city or government protection. There is no coordination of beach trips at the school or district level, and they come from as far out as Abbotsford and North Vancouver

    In 2009, there was a letter to the Now Editor regarding the destruction of White Rock beach by the same cause. Click here to read.
     

    Midshipman
    This is a MALE midshipman guarding a nest of eggs. We just removed the rock with the eggs on it which was the roof of the male’s nest. It is very important to put the roof back on with the eggs facing down where they will be recovered with water.
    The eggs are bright yellow before they hatch and a transparent white after hatched.
    Midshipman instinctively burrow when the roof of their nest is lifted.
     
    Midshipman nests are usually underwater. However, low tides below 1 m often expose them. This male is gasping for oxygen, but it is adapted to survive a few hours in the air.
    These caring kids are pouring water on the midshipman to give it some oxygen and keep it moist. This was a very low tide exposing the male for almost 5 hours.
     
    DO NOT MOVE OR DISTURB this fish. It is guarding a nest.



     

     

    Beach Etiquette

    View and print your copy of our Beach Etiquette poster for your classroom. Click here

    Crabs are the most often seen creature on the beach. On healthy beaches there are at least 6 species of crab living in the different intertidal zones defined by how often the tide is out. ALL crabs hide when uncovered by water. If they can’t find a rock to squeeze under, they dig themselves down into the moist sand.

    Shore and hermit crabs are found high up the beach, at the backshore, in pockets of water under rocks. Dungeness and red rock might be found in the middle sandy zone, but they are unhappily stranded. They prefer to stay out under water in the subtidal zone. In the subtidal eelgrass meadow, kelp and hairy helmet crabs are found. They have long fragile legs that gulls can rip off easily, so they certainly don’t like being exposed.

    Click here to print your Crab ID sheet.