Prof Peter Nelson will discuss the effects of atmospheric contaminants and current understanding of the sources, transport and fate of atmospheric contaminants such as fine particles and mercury by reference to national and global studies.

After our AGM, Ross Rapmund will give a talk about the bird life of northern Sydney.

This walk will focus on the bird diversity found along the Lane Cove River corridor downstream of the tidal weir, including the delightful Mowbray Park area.

STEP will run a site in the usual location near Thornleigh oval focusing on rubbish near Lane Cove National Park and the Comenarra Parkway.

Michael Scollay’s talk takes a tour of earth’s climate past to see if there are any useful analogies to what is happening to earth’s climate today.

Professor Paul Boon has just finished writing a book on the Hawkesbury – no one has done this before! It will be published in July 2017.

STEP has concerns that the project to fill Hornsby Quarry with spoil from the North Connex tunnel and create public recreation spaces will ignore the unique geological feature, the volcanic diatreme. In this talk Dr Ian Percival, who prepared the original geoheritage report on the Hornsby diatreme in 1979, will outline the geology of the feature, explain its origin, and will argue why it should be protected for future generations of geologists and the public. Ian is Senior Principal Research Scientist (Paleontologist) at the Geological Survey of NSW.

Graham Wegener, Project Coordinator at Wahroonga Waterways Landcare will talk about their work caring for the bushland at the Wahroonga Estate. They also manage a number of education and community engagement programs.

Agnes Banks Nature Reserve is unique in the Sydney area and a wonderful place for wildflowers in both spring and autumn. It's unique because it consists largely of white dune sand, even though it's 60 km from the coast!

This interesting walk covers a wide range of vegetation communities including gallery rainforest, tall open forest, dry sclerophyll, mangrove and salt marsh with attractive views of Middle Harbour.

We will walk to City View Lookout via Lorna Pass through varied forest and views of Lane Cove River.

Circuit walk to Marie Byles Lookout, Putty Beach, Gerrin Point, Maitland Beach and then a climb back to the start.