Irish Moss Photo Gallery
Irish moss (Chondrus crispus) is a very common, and commercially important seaweed in Atlantic Canada. A 'red algae' growing in lower rocky intertidal zones with wave action and subtidal zones with less water movement, Irish moss displays a wide range of colors, depending on nutrient availability and light stimulation. The best fertilized Irish moss is a deep purplish-brown with tiny bright blue glints, and pigmentation declines with nutrient availability. Simply noting that Irish moss is green or yellow does not indicate an unusual condition, since this plant has always managed to grow in habitat with lower nutrient availability where these lighter colors will normally occur. But when habitat that once supported thick, deep-purple moss now produces only short yellow plants, a decline in nutrient availability is suggested. That is what I have found; where I raked thick dark moss in summer 30 years ago, there now grows only very short, pale greenish-gold plants. And along the Atlantic coast of Nova Scotia in general, areas where moss-raking is feasible have been shrinking. (More discussion and pictures of Irish moss are in the recently added page on the shifting baseline of color in Irish moss, and the original seaweed article.)
All photos copyright Debbie MacKenzie. Reproduce them if you like, just please credit the source.