It must be a Moulting Week for Dungeness Crab Juveniles

A surprizing number of carapaces from molting Dungeness Crabs turned up in the strand line on Taylor Beach this past week.  Synchronicity of molting may provide an advantage here are a few speculative ideas:

1. There may be a release of gametes from other invertebrates that would provide  a ready food source,

2. It may be to overwhelm predators so that a few crabs survive when they are vulnerable in their soft shell phase , before exoskeleton hardening.

3. Availability of many individuals of a population at once to predators may increase the survivability of those that manage to escape being caught.

4. Its just timing.. they all may have come from the same age egg batch and given constant conditions, have all matured at the same time.

The Fat Gaper: Tresus capax on Taylor Beach

We often come across these empty shells of  Tresus capax the Fat Gaper on the shores of Taylor Beach. They live buried in the sand in the shallow water offshore. Around the opening of the siphon, Tresus capax  has small palps around each opening which distinguishes it from other bivalves.

Pacific Geoduck, Panopea abrupta

Fat Gaper : ( Tresus capax)

Classification::
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Veneroida
Family: Mactridae
Genus: Tresus
Species: Tresus capax (Gould, 1850)

fat gaper

The Fat Gaper, Tresus capax . Note the size in comparison to a glove.

Useful References: E-fauna BC page on bivalve Molluscs:

 

Pododesmus (Monia) macroschisma

The false pacific jingle shell, or rock oyster, often comes ashore on Taylor Beach attached to the holdfasts of kelp.

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Various species of kelp have attached their holdfasts to this rock oyster shell, leading to it being detached and carried ashore on Taylor Beach.

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One of the valves of Pododesmus sp.

 

Pododesmus (Monia) macroschisma (Deshayes, 1839)

 

Reference: Peter’s seashells

 

Octopus (Enteroctopus dofleini) on Taylor Beach

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The remains of an Octopus on Taylor Beach

Not a great picture but the remains of evidence that offshore of Taylor Beach, the giant pacific octopus goes through its life cycle, which is very short.. just a few years.

rmoctopus3See the entry on the Race Rocks website for the octopus

Domain: Eukarya
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Octopoda
Suborder: Incirrata
Family: Octopodidae
Genus: Enteroctopus
Species: dofleini (Hochberg, 1998)
Common Name Giant Pacific Octopus

The Hooded nudibranch: Melibe leonina

Laura Verhegge has posted this note about Melibe leonina, seen today in Pedder Bay  on the Pearson College Marine Science website

A multitude of Melibe drift to the Pearson College dock

melibe

Melibe the hooded nudibranch photo by Laura Verhegge

melibe3

Melibe leonina photos on Race Rocks Taxonomy by Ryan Murphy

 

(see other images and a video of the movement on her website)

 

 

 

 

Ryan Murphy got these images for the  Race Rocks Taxonomy.

 

 

 

 

 

Domain: Eukarya
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Opisthobranchia
Order: Nudibranchia
Superfamily: Tritoniodea
Family: Tethydidae
Genus: Melibe
Species: leonina Gould, 1852
Common Name: Hooded Nudibranch

Seabirds abundant on Taylor Beach today

I had thought that the Mergansers which started showing up on Taylor Beach this past week were Common Merganser females. Now I am not so sure, as most of them lok more like Red-breasted merganser females . Click for enlargement.

merganser females

Group of female Mergansers off the north end of Taylor Beach

merganserfemaleclose

Zoomed in view of mergansers- possibly a mix of mainly red-breasted merganser females and common merganser females..

flyingcorm

Flying merganser females

flyingmergansersclose

Flying merganser females closer–

buffleheads

Buffleheads in large flocks of up to 100 individuals

buffleandcorm

Flying Buffleheads go past Double -crested Cormorants

shipand cormorants

Double-crested Cormorants with an ocean-going vessel in the background. If all projects for the Pacific North-west go ahead as planned, over 1000 more ships of this size above the high number already using this waterway, will be transiting these waters each year, all carrying bunker and diesel fuel and if Kinder Morgan has its way 350 a year carrying highly toxic dilbit. Click on the oil-spill risk category link below.

See the Census Page on the seabirds showing up in the last few weeks.

The Shoreline of Metchosin: What do we have to lose with tanker traffic

Along the shoreline of Metchosin and underwater we have ecosystems which are at risk of being heavily impacted in the event of an impending oil spill catastrophe given all the proposed projects which will increase ship traffic to unacceptable levels in the Strait of Juan de Fuca. The presentation by Garry Fletcher linked here was done on the evening of October 23rd, 2014 at the Metchosin Community Hall organized by Karyn Woodland and the local Dogwood Initiative Group. ( NOTE: comments are included under the images and all images are copyright of the photographers who took them, John Harper(GeoBC); the ecoguardians at Race Rocks: Ryan Murphy, Raisa Mirza, Alex Fletcher, Anne Stewart, Adam Harding, Mike Robinson and Courtenay Edwards, and myself. The graphics from the first part on Oil Spill Risk are from  posts of Nov.4 on Oil Spill Risks
Link to a description of the three presentations to the Town hall meeting by Kai Nagata of the Dogwood Initiative, Andrew Weaver, Green Party MLA for Oak Bay and Intervenor in the Kinder Morgan hearings, and Garry Fletcher, Intervenor for the Board of Friends of Ecological Reserves in the Kinder-Morgan / Trans Mountain Expansion project hearings. gfpresent

Sharing our Shoreline

Values and Views
Island Trust Communities
Marine By Nature
The Islands within the Salish Sea have been  shaped by ancient glaciers and modern oceanic forces. Whether you visit the islands seasonally or live here year round, Islanders treasure the marine environment.  The North Pender Local Trust Committee has developed this brochure to introduce you to where sensitive marine habitats exist, how you can recognize them, and what simple steps you can take to ensure our local waters continue to support a vibrant and abundant marine ecosystem.

This PDF has been produced by the North Pender Island Local Trust Committee: Sharing Our shorelines_lowres

IslandstrustContents:

Clean Water
Shoreline erosion
Coastal Bluffs and Shoreline beaches
Marine Riparian Vegetation
Intertidal Habitats
Beach-spawning Forage Fish
Eelgrass habitats
Kelp Forests and Rocky Reefs
Marine shorelines as critical fish habitats

Tonicella lineata–Lined chiton

Tonicella lineata, the lined chiton : These photos taken in May, 2013 were submitted by Gretchen Markle . They were taken on the area known as Laird’s Beach  (on Parry Bay south of Taylor Road)

gmtonicella

Kingdom: Animalia
Phylum: Mollusca
Class: Polyplacophora
Order: Neoloricata
Family: Ischnochitonidae
Genus: Tonicella
Species: T. lineata
Binomial name:Tonicella lineata , Wood, 1815

Cryptolithoides sitchensis–turtle crab

Cryptolithoides sitchensis, the turtle crab : These photos taken in May, 2013 were submitted by Gretchen Markle . They were taken on the area known as Laird’s Beach  (on Parry Bay south of Taylor Road)

gmturtlecrab gmturtlecrab2p1030812Also see another more colourful example of this species found  at Christopher Point by a diving student in the Pearson College Marine Science class in October, 2014

 
Cryptolithoides sitchensis, turtle crab
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Infraorder: Anomura
Family: Lithodidae
Genus: Cryptolithodes
Species: C. sitchensis
Cryptolithodes sitchensis (Brandt, 1853 [1]