Tag Archives: stonecrop

Warden’s report Race Rocks September 2017

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I was able to get out to Race Rocks Ecological reserve with Guy today and went with former student Joao Luis de Castro and Yan Corriveau. I  wanted to check on what changes have occurred on Great Race Rock Island  since my last visit. Since it was an exceptionally dry summer, the effect on vegetation was evident. The spread of hauled out sealions into parts of the island traditionally not invaded also has left a significant impact on vegetation. It will be important to  follow up on vegetation recovery once the rains start.

This year the sea lions have hauled out and inhabited many parts of the island formerly not used as a haulout . I am concerned that erosion because of obliteration of most of the plants in the area of the First Nations burial cairns could be detrimental to the cairns. It will be inprtant to check on this once the sealions have left again.

The lack of precipitation since May has resulted in a shrinking of the stonecrop that covers the top of the Reservoir. I had never seen it quite this dry before.

 

The sealion haulouts at Race Rocks do not segregate by species as they do in some other parts of the coast. Note the cookie-cutter shark bites on the California Sealion on the right hand picture.

 

Garry Fletcher, Sept 25, 2017

Sedum anglicum, English Stonecrop–The Race Rocks Taxonomy

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stonecrop

Sedum anglicum,(in bloom in July,) English Stonecrop– invasive at Race Rocks

 

Englishstonecrop

Sedum anglicum, English Stonecrop all photos by Garry Fletcher

This plant was introduced to Race Rocks by Assistant keepers in the 1980s. From a small flower bed near the assistant’s house It has spread over much of the Great Race Rock Island. Since it is a member of the Crassulacea family, it uses the crassulacean acid metabolism (CAM) method for fixation of

The crevices of the rock outcrops where native grasses grew are being invaded by this stonecrop.

The crevices of the rock outcrops where native grasses grew are being invaded by this stonecrop.

Carbon Dioxide for photosynthesis. Since it can fix Carbon into a chemical when stomata are open only when its cool at night, it is very resistant to drought, and can survive with very little soil.

stonecrop_cistern

The mat of green is a monoculture of Sedum anglicum, English Stonecrop growing on the concrete surface of the large gound-level cistern.

It is of course not the only introduced species on Race Rocks but since it is not grazed by anything, it is rapidly replacing the sparse growth of native species such as thrift  and grasses in the rock crevices.
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
Order: Saxifragales
Family: Crassulaceae
Genus: Sedum
Species: S. anglicum
English Stonecrop
Other Angiosperms (flowering plants) at Race Rock

taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams.