Phenology and temperature tolerance of the red algae Chondria baileyana, Lomentaria baileyana, Griffithsia globifera, and Dasya baillouviana in Nova Scotia

The warm-temperate species Chondria baileyana, Lomentaria baileyana, Griffithsia globifera, and Dasya baillouviana are restricted, north of Cape Cod on the eastern American coast, to embayments and estuaries. The northern limit of distribution is the southern Gulf of St. Lawrence. In culture, isolates of these species from Nova Scotia survived 28 to 34 °C. In the field all reproduced during the period of maximum temperature, and in G. globifera and C. baileyana the progeny also reproduced. Some of the progeny of D. baillouviana developed as cold- and heat-resistant pads that survived the winter, whereas the other three species died back to perennating holdfast structures. Lomentaria baileyana was the least successful of the group, being unable to form resistant holdfast pads in midsummer temperatures and having the most limited reproductive period and smallest population size.