Plea from a breeding colony of Pelagic Cormorants to the City of Vancouver

In late 2015 or early 2016 City of Vancouver authorities installed netting beneath the central span of the Burrard Bridge.

Photo from end of December 2017

This measure was taken to intercept any bits of concrete, tools, or other hard objects caused to fall by the road work which was carried out between February of 2016 and October of 2017. The placement of that netting deprived the Burrard Bridge breeding colony of Pelagic Cormorants of the nest sites in the bridge understructure they had been using since the year 2000. See video below from the summer of 2015 showing fledglings from that colony doing flight practice.

The construction on the Burrard Bridge roadbed has been completed. The reason for installation of that netting no longer exists. Yet, as of this writing it has not been removed. It would be wonderful to get that done before breeding season of 2018, if any thought at all is given to welfare of our south coast Pelagic Cormorants. On the Granville Bridge much of the beeding colony is on hand by the first of February, similarly early February for the Pelagic Cormorants at the Ironworkers Memorial Bridge.

Vancouver’s bridge Pelagic Cormorant breeding colonies (Burrard, Granville, Ironworkers Memorial) account for the majority of Pelagic Cormorants known to breed on BC’s lower coast. What recent surveys have been carried out show that their numbers along the southwest coast (and higher) have steeply declined since the late 1980s, with many historical breeding locations abandoned. See: Carter2014(SunshineCoast-VancouverBridges)(FinalReport)

One such historical rookery was the basalt cliffs between Prospect Point and Siwash Rock in Stanley Park, last known to be used for nesting by Pelagic Cormorants (12 nests) in the year 2000. Reasons for abandonment as a breeding site? One: increased traffic along the seawall pursuant to the twinning of lanes to acccomodate bicycles, roller blades, and skate boards as well as pedestrians. The foreshore beneath the cliffs has become an unsafe fledgling cormorant kindergarten. The birds need a stretch of almost three months in the summer having a relatively worry-free foreshore to accomodate the weak, newly fledged young from early to late hatches during breeding season. Two: danger from increased ferocity of wind and weather driven by global warming. Three: vulnerability to predation by Vancouver’s Bald Eagles. In recent years the cliffs have ceased to be used for roosting at all (no guano to be seen).

The greater safety from human disturbance, violent weather events, and eagle predation offered by Vancouver’s bridges should be given to the cormorants. Especially in a city that trumpets having an official Bird Strategy (since 2015) that claims to be endeavouring to “create conditions for native birds to thrive in Vancouver.”

UPDATE:

On 5 January 2018, David Currie, City of Vancouver Engineering, e-mailed me an informative reply to a letter I sent regarding this matter. The meat of it is quoted below:

[EXCERPT]
The City retained experts in this field (Golder Associates) to review the project, assess the existing habitat and develop an exclusion netting and monitoring plan. That plan was reviewed and modified to include the feedback we received from provincial wildlife experts.  The bird netting was installed in 2015 after the nesting season was over, and Golder conducted surveys on both the Granville Bridge and the Burrard Bridge in 2015, 2016 and 2017.  The monitoring results (copy of report attached) indicate that there was a relocation from Burrard to Granville and that the nesting numbers have increased significantly in 2017.  Golder also advises that there is space for additional nests on the Granville Bridge. 
 
Please note that our current Burrard Bridge contractor removed the bird exclusion netting above the Aquatic Centre parking lot late last year.

 The City will be replacing the Marine Fenders for the Burrard Bridge in 2018. The City also needs to repaint the structural steel portion of the Burrard Bridge (the section between the two main towers) in the next few years. The repainting work would require the removal of any nests that are located in the structural steel portion of the Burrard Bridge. The retention of the bird exclusion netting in the structural steel portion of the Burrard Bridge would ensure that nesting cormorants are not disturbed a second time. A decision on when the bird exclusion netting under the steel structure will be removed will be made once the timing of the steel structure repainting has been determined. 
[END EXCERPT]

In short, the City does not plan to give the Pelagic Cormorants their mid-bridge breeding site back any time soon. But the City obviously recognises the bridge’s function as breeding habitat. I hope that is reassuring, and that the convenience of a nestless bridge for ease of bridge maintenance will not suddenly overrule. The question of where else the birds can go will become more and more problematic for our Pelagic Cormorants as time goes on.

***********

WordPress threatens to be placing advertisements in this space. The ads will be governed by their algorithms, I have no say.  My apologies.

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