Clean beach at Sand Cove. Decades ago when snails and small fish were plentiful here (unlike now), nothing green was visible in this intertidal zone.

Bright green Ulva grows in lower intertidal zone of clean N.S. beach, early summer. Nothing green grew here decades ago.

Enteromorpha is abundant in the same area.

Late summer on the clean beach, Ulva shows a paler green color.

10-20 feet below low tide level in outer Shad Bay (clean) in mid-summer. Covered with filamentous green growth - Cladophora?

Mid-summer codium fragile with prominent colorless hairs, a signal of nutrient shortage (agreeing with the yellow Irish moss in the background.)

Wooly, fine green growths in area with pale rockweed.

Short pale Irish moss overgrown by fine green growth.

Bright green growth with gas bubbles growing as epiphyte on pale rockweed (Ascophyllum).

In areas with more wave action, green growth exposed with pale Irish moss at low tide.

Greenish rockweed, pale green and 'hairy' Codium, plus drifting pale green fluff.

Fine green growths flourish while subtidal rockweed pales and breaks down.

Bright green algae, low on a clean beach, midsummer, on a rock with yellowed and deteriorating Fucus.

Dark green Ulva, dark Fucus, and white barnacles in heavily polluted Halifax Harbour in early October.

Hairy codium, green fuzz, yellow rockweeds and pale, "burnt" kelp coexist.

In sewage-polluted Halifax Harbour, N.S. a fine green growth in the upper intertidal zone.

Paper-thin annual green growth on clean beach in mid-summer.

A transient green growth appears in the spray zone in springtime. This is also new.

Green, slimy, filamentous growth now grows over barnacles along a clean N.S. coast in early summer.