These slick brown plains may look desolate, alien even, but under all of that muck the mudflats are teeming with life.
Each day, high tides obscure the mudflats and deposit a layer of mud, clay, and silt once the water inevitably retreats. New Brunswick’s powerful tides create the perfect environment to foster these vast fields of rich brown mud. In some areas around the province, they can stretch up to 2km offshore at low tide.
High levels of bacteria and decomposing organic matter give the mudflats their characteristic rotten egg smell. Sounds appealing, right? Plenty of native critters would say so. Get close enough to the mud, and you will probably begin to get a sense of the diverse communities of invertebrates that have taken up residence here—though many species are too small for the human eye to detect. At the bottom of the food chain, diatoms and other algae sustain a variety of mollusks, crustaceans, and worms all of which have evolved the miraculous ability to thrive under these environmental extremes. The mud shrimp, a tiny crustacean roughly the size of a grain of rice, can be observed in concentrations as high as 60,000 per one square meter of mud. When the tide rises over the mudflats, flatfish, eels, crabs, sea ducks and more take advantage of this abundance.
While these creatures are interesting, they are often all but overshadowed by the unofficial star of the mudflats— the Semipalmated Sandpiper. Being both incredibly cute and incredibly impressive, the return of the sandpipers is a welcome sight to most.
Photo via. Nature Conservancy Canada
Johnson’s Mills is a beach located near Dorchester featuring extensive mudflats. Once a year between July to early August, this quiet beach is transformed into a veritable food court by a frenzy of scurrying sandpipers. Over 30% of the world’s population of semipalmated sandpipers will stop at Johnson’s Mills over the course of their journey. These tiny birds are on a dire mission to consume as many calories as possible before the water rises once again; the mudflats are a vital pitstop en route between their arctic summer nesting grounds and South America. This colossal trip can be well over 3000km over the course of a few days’ worth of non-stop flying. In order to succeed, sandpipers must nearly double their body weight to store enough energy.
Mudflats are an oasis for fatigued birds. Sandpipers gorge themselves on biofilm (composed of bacteria and diatoms) and the abundant, nutrient-dense shrimp until they feel they are ready to continue. Globally, mudflats are among the most rapidly disappearing environments. Between 1984 and 2016, one-sixth of all mudflats disappeared as a result of land use changes, land reclamation, and coastal development. Arne Lesterhuis, WHSRN Shorebird Monitoring and Conservation Specialist explains that “coastal infrastructure is often located near high-quality foraging areas for shorebirds, such as river estuaries.” A hardening shoreline spells disaster for exhausted shorebirds in search of vital sustenance. Even Canada’s Ministry of Environment has acknowledged that the consequences for shorebirds could be “potentially high in magnitude, permanent, irreversible, and continuous.”
One of the goals of this series is to highlight significant sites throughout the watershed, especially those that are undervalued or ignored. Through its environmental work, the PWA hopes to shed light on the value of preserving all of the diverse ecosystems in our watershed. Mudflats deserve to be recognized for what they are, diverse ecosystems vital for the continued existence of many species. Mudflats may not have the same visceral appeal as coral reefs, rainforests, or nice sandy beaches, but they are no less important.
In the poetic words of nature writer James Lowen, developing an appreciation for mudflats made it so that the “odor rising from [his] feet no longer seems sulphuric, but fragrant.”
Jhonson’s Mills Interpretive Center: Johnson’s 3K8, Dorchester Cape Rd, Johnson’s Mills, NB
45.834082609462214, -64.51150523162653
Want me to feature one of your favorite spots in the watershed? Email your suggestions to communications@petitcodiacwatershed.org
