BTB Reader Elizabeth Ruth Dutton Butcher sent us these photos, which she took at Burien’s Seahurst Park beach on Thursday, May 28, showing what is most likely an active algal bloom caused by Noctiluca, a non-toxic form of zooplankton, which feed on phytoplankton: 20150528_104255 20150528_104055 20150528_104929 According to the State Department of Ecology:

Spring and summer are the time of year when sunshine and warm temperatures aren’t just making our lawns and garden plants grow, but are also contributing to algae blooms in our marine waters. An algae bloom is the visible appearance of millions of tiny plant-like organisms in the water. These tiny algae, or phytoplankton are present all year. The recipe for blooms is abundant sunlight, nutrients and the right water conditions. Noctiluca visibly aggregate at the sea surface as part of their life cycle and feeding strategy. The nontoxic Noctiluca blooms usually appear as a rusty reddish color like tomato soup and are common in Puget Sound.