Northern Territory

The main climate pressures affecting the marine environment in the Northern Territory are increasing ocean temperature, the frequency and intensity of storms (cyclones) and ocean acidity. Understanding the effects of these changes can assist in understanding the likely impacts to coastal communities.

Increasing ocean temperatures negatively impact commercial, recreational and charter fishing as well as marine tourism (diving). These impacts are due to potential species range shifts, forcing some valuable and iconic species to move further south into cooler waters. Warmer waters may also increase the prevalence and survival of pests and diseases which can have negative impacts on all fisheries, marine tourism and shipping, ports and marinas. Additional regulations may be placed on shipping, and monitoring/remediation may be required to deal with pests and diseases in ports and marinas.

Storms, in particular cyclones, can negatively affect land- and pen-based aquaculture through damage to infrastructure such as barramundi ponds, and stress to pearl oysters. Marine tourism (dive and fishing charters) are also negatively affected by storms through direct damage to corals and mangroves, and through reduction of the number of days businesses are able to operate. In addition, increased ocean acidity reduces coral growth and can negatively impact dive charters that specialise in coral reef diving.

High value species

Commercial wild capture fisheries in the Northern Territory had the lowest production (5315 t) and value (over $32m) of all Australian states, likely due to the small resident population (in 2010/11).

Crabs were the most valuable commercial species (almost $8m) followed by saddletail snapper ($5.3m) and barramundi (almost $5m). Saddletail snapper had the highest production (1114 t in 2010/11), with shark (891 t) and barramundi (707 t) ranking second and third. Crab production was substantially lower production at 391 t.

Aquaculture

The aquaculture sector in the Northern Territory is very small with only two main species farmed (as of 2010/11). In 2010/11, pearl oysters and barramundi were valued at approximately $21m and $5m, respectively. Production of barramundi in 2010/11 was 651 t. At the time of writing, statistics for pearl oyster production were not available.

Recreational fishing

According to Henry and Lyle (2003), participation rates in recreational and indigenous fishing in the Northern Territory are the highest in Australia. Almost 32% of the NT population participated in recreational or indigenous fishing between May 1999 and May 2000. These fishers catch mainly barramundi, mulloway/jewfish and sea perch.

Other sectors

In addition to fishing and aquaculture, the Northern Territory has an active shipping/sea freight industry as well as employment in ports and yacht clubs.

Climate and sealife