Sources of change to the connectivity:

• Habitat removal for a variety of reasons, such as buildings, foreshore development, roads, bridges and hydrological modification (e.g. reclamation, bund walls) increases habitat fragmentation and thus reduces habitat connectivity.
• Occasionally human activities such as drainage modification may increase connectivity between wetlands.
• Stream barriers such as dams, weirs, flood gates and culverts can have a significant effect on connectivity by physically preventing movement of biota.
• Larger impoundments affect connectivity by reducing the frequency and extent of bank overtopping which under natural conditions recharges off-stream wetlands and allows biota to move in and out of the wetlands, e.g. a loss of lateral connectivity between rivers and billabongs.
• A loss of connectivity can also result in a change in the natural movement of materials such as ions, nutrients, organic matter and sediments.
• Physical barriers are not the only factors impacting connectivity, e.g. poor water quality can stop animals from accessing areas of habitat.