LONG-TERM CHANGES IN THE MARINE MACROALGAE OF 3 POLLUTED ESTUARIES IN NORTHEAST ENGLAND

Comparisons are made of the current status of macroalgae in the Tyne, Wear and Tees estuaries with that from earlier surveys, some 20 and 60 years ago. Brown and red seaweeds have evidently decreased in diversity since the early 1930s in the Tees estuary, and during the past 20 or so years in the Tyne and Wear estuaries. Species losses have, however, been compensated for in part by increased numbers of green and blue-green algae in the sewage-polluted Tyne and Tees estuaries. There are nevertheless some signs of recovery of macroalgal populations following recent clean-up measures. Species have recolonised part of the Tees which was devoid of macroalgae in the 1970s, and brown algae have spread into higher reaches of the Wear estuary over the same period of time.