Warden’s report -Visit to ER #76 – Fraser River Islands, March 31, 2007

Posted March 31, 2007 | Categories : 76,Invasive Species,Research,Species List,Warden Reports |

Visit to ER #76 – Fraser River Islands, March 31, 2007

Sunny, but cold day, with temperatures down to 0 degrees overnight in Vancouver, up to about 9 degrees in day. Fresh snow on higher mountains (like Cheam), on top of existing high snowpack. Some wind. Water level low, around 1 metre at Mission.

Departed Deroche Boat Launch Ramp around 10:30 am. Gate locked at access road before dyke, so we carried kayaks to the launch. Water level low enough that we could paddle around lower ends of gravel bars, and ferry across channels without losing too much distance, so did not have to portage upriver on gravel bars. Landed at largest island, below oldest cottonwood grouping on former small island, now with eagle nest. There was a mature bald eagle perched near nest and another in the nest.

This trip we tried to locate the four vegetation plots that were established in 1983 by Dr Fred Bunnell and students, and with further inventory by former warden, Anthea Farr. Anthea had just passed onto us a file with this material in March, and so we were attempting to find these plots, based on sketch map, metal markers on trees and upright hockey stick markers.

Plot #4 was in the larger cottonwood, and we began to traverse through this section looking for the plot. We soon came upon a mass of white feathers. Strange as there were no bones, just body feathers, wing and tail feathers, likely from a gull. We reached a point where we did not want to approach closer to the eagle on the nest, and so we stopped looking for the plot. We then followed the old swale in an eastern direction to the stand of youngest cottonwood, looking for plot #1. However, the understorey in this area was salmonberry interspersed with Himalayan blackberry, which made the bushwhacking difficult. The leaves on the salmonberry were just emerging, so the visibility was good, but the brambles made the walking very difficult. After about a half hour, without making much progress we detoured and followed the easier route of another former swale curving to the southeast. We could not see the red tailed hawk nest that Anthea had indicated on her map, but we did see a pair of red tailed hawk perching, crying and flying about a couple of times during the day. On reaching the deep inner slough, we walked north along it, towards the beaver house, but couldn’t get right close to it. We did find deteriorating pairs of blue rubber gloves, in four different locations. These might have come from people harvesting equisetum. We also tried to find plot #2, but could not. We did find a tree with board steps nailed onto it, that one could climb up on to about ten feet high. This was in the area where the hawk nest was shown, in older cottonwood and birch, with understorey of salmonberry and Himalayan blackberry.

Next we continued southwest, downriver on the main dry channel between the two islands, and attempted to locate plot #3. This appears to be in the area where we had found the marijuana growing with the piped water feed. Again could not find the plot, and fortunately no sign of anyone returning to this area.

Along the main dry channel there was a layer of fine silt, likely left from the high water of November. In a couple of places, we saw tracks, which were cat family as no claw

marks showed in the fine silt layer. The tracks looked too big for a domestic cat, and too small for a cougar, and we wondered about bobcat. (Anthea Farr concurred after viewing photo of tracks.) Near the downstream end of that channel, on the biggest island, is a beaver house of sticks lying against the bank, now dry. We walked downstream quite a distance on accreting gravels/sands as these islands seem to be enlarging at the downstream end. The large downstream island facing the main river channel and Chilliwack Mountain is eroding on its south side

The channel between the downstream tip of the larger island and to the northwest is where there were again many waterfowl. There were about 20 double-crested cormorants standing on a log grounded in the channel and about 200 mallards sunning on a gravel bar across the channel.

Walking back to the tip of that northern island, just into the vegetation of the willow and grasses, there were about four areas of scattered white gull feathers. Again no bones were visible, just the feathers. We began to wonder whether a bobcat was catching sleeping gulls on the sand spit, carrying them to cover of shore, and plucking off some feathers before eating the entire bird.

We continued walking upriver along the northwest side, returned to our boats and paddled back to the boat launch, arriving at our vehicle around 5:30 pm.


Tall Oregan Grape, in flower Mahonia aquifolium

Black Cottonwood, Populus balsamifera ssp. trichocarpa

Red Alder, Alnus rubra

Willow, sp

Douglas fir, Pseudotsuga menziesii

Western red cedar, Thuya plicata


Bitter cherry, Prunus emarginata


Salmonberry, leafing out, Rugus spectabilis

Snowberry, already leafed out, Symphoricarpos albus

Indian plum, Oemleria cerasiformis


Elderberry. Sambucus racemosa

Green osier dogwood

Red osier dogwood

Black hawthorn, with thorns, Crataegus douglasii

Invasive Vegetation

English ivy growing up one tree, visible from old swale near hawk’s former nest

Holly (

Himalayan blackberry, Rubus discolor; in several areas too extensive for removal