SAMWMA, by BCMELP, from BCWW ...

... If they could have thought up a longer, more unwieldy acronym, I'm sure they would have used it. Government bureaucracies are good at that.

It stands for South Arm Marshes Wildlife Management Area, managed by the British Columbia Ministry of Environment, Lands and Parks, described by British Columbian Wildlife Watch. The SAMWMA is the marshland area mostly enclosed and criss-crossed by the alternate channels of the Fraser River on this map, below. Ladner Harbour is at the anchor on the south bank, Finn Slough at the northern anchor, Reifel Migratory Bird Sanctuary at the western shore, where the pair of walkers are. The area shown in the map is all flat delta.

I'm going to steal wholesale from BCWildlifeWatch's page; it has some good, relevant information.

(SAMWMA) contains 937 hectares (2316 acres) of habitats critically important to fish and wildlife populations. (It) ... contains a series of islands surrounded by both freshwater and intertidal marshes. Included in SAMWMA are Ladner Marsh, Ladner Lagoon and seven main islands - Woodward, Barber, Duck, Kirkland, Rose, Gunn and Williamson. ... SAMWMA is located directly east of Alaksen National Wildlife Area and the George C. Reifel Migratory Bird Sanctuary.
...
The Fraser River estuary is the single most important area of aquatic bird and raptor migration and wintering habitat in British Columbia. The South Arm Marshes Wildlife Management Area provides wintering, migration and breeding habitats for waterfowl, shorebirds, raptors and many passerine species. In addition, the intertidal marshes provide critical rearing areas for juvenile salmon.

Historically, more than 70% of the natural habitat in the Fraser River estuary has been lost to dyking. The islands and marshes of SAMWMA contain an estimated 25% of the remaining estuary marsh habitat. As these habitats continue to be lost to, or impacted by, urban development, this management area becomes increasingly more important as wildlife and fish habitat.

They include a list of commonly observed wildlife in this area:

Loons and Grebes - Common Loon, Red-throated Loon, Horned Grebe, Red-necked Grebe and Western Grebe.
Great Blue Heron.
Other Waterfowl - The most common species include Mallard, Northern Pintail, Green-winged Teal and American Widgeon. Snow Goose are present in large numbers on the west portion of the area in March and April.
Bald Eagle.
Hawks - Northern Harrier, Red-tailed Hawk, Sharp-shinned Hawk and Cooper's Hawk.
Peregrine Falcon
Shorebirds
Songbirds - Easily observed are the Marsh Wren, Red-winged Blackbird and Song Sparrow.
Mammals - Beaver and Muskrat,Coyotes, Raccoons and Mink
Harbour Seal and California Sea Lions.

Unused pilings, marsh grasses.

And they forgot the ever-present seagulls, the crows, the starlings, Violet-green swallow, Sandhill Cranes, Canada goose, to mention those that come quickly to mind. And the rabbits and skunks, frogs, snakes, and assorted small rodents.

Never mind; the point is that these banks and islands are bursting with life. And are being gradually eaten away by our growing population.

Blackberries, green, pink, red and almost black.

The delta, like all riparian environments, is a fickle hostess; sloughs fill in, streams change course, the river periodically leaps out of its bed and romps over the tidy farms, tearing down and building up according to its whim of the moment. Not for nothing are older homes in Richmond and the Delta flatlands build high above ground, with the "basement" at ground level. There's a sensible reason for those deep, wide ditches, trenches you could lose a car in, throughout the area; they attempt to channel those spring floods out to sea, where they belong.

Year after year I have watched, a bit inland from this map, near Cloverdale, large fields that stay underwater from fall until spring, so that the road seems to be crossing a lake. In the summertime, it's all in hay and pasture.

Over the centuries, the river has been terraforming; chewing up the rocks from the mountains and spitting them out at the seashore, spreading them out flat and wide, deep into the strait itself (look at the lighter area underwater on the map). And the ocean fights back, pushing its tides well up the river; you can see the water flowing upstream as far away as Mission, only to turn an hour later and speed westward again.

We live in a continual to-ing and fro-ing of water, salt, fresh and brackish.

Great country for waterfowl.

But besides the usual uncertainties of the terrain and the encroachment of human habitat, a new challenge faces the inhabitants of the marshland and rivers. I'll talk about it in the next post.