Avon Heathcote Estuary Fishing Christchurch – Unrealised Opportunities

Avon Heathcote Estuary / Te Ihutai

By Peter Langlands

The Avon Heathcote Estuary is a jewel in the crown of Christchurch’s recreational areas. Situated only ten minutes drive from the city’s centre. The Avon Heathcote Estuary is a powerhouse for wildlife.

The estuary is sheltered from the coastline of Pegasus Bay by Brighton Spit. Well-defined river channels drain the estuary and all the water rips through the estuary’s mouth at Shag Rock.

The Avon-Heathcote has a wide range of habitats for fish from the freshwater rivers to silty mud flats where sand flounders feed, to deep channels and a rocky shore along Moncks Bay where the sea floods into the estuary.

Twenty-eight species of fish have been found in the Avon-Heathcote Estuary.

The estuary has large populations of sand flounders and yellow-eyed mullet. Many species visit the estuary as part of spawning cycles, such as the flounders, which use the estuary as a nursery area.

Other fish visit the estuary to feed on its rich marine life such as sandworms and shrimps and shellfish beds.

A study in 1968 found that sand flounder, yellow-eyed mullet, yellow-bellied flounder, common sole, kahawai and spotties made up 90 per cent of the estuary fish population. Indeed flatfish are prolific in the estuaries’ waters. From time to time oceanic fish such as tuna, sharks, swordfish and frostfish end up in the estuary as vagrants.

Over recent years thresher sharks have been regularly caught in set nets placed next to the estuaries entrance into Pegasus Bay. Freshwater fish such as brown trout pass through the estuary on their way to the Avon River after feeding in coastal waters.

Avon Heathcote Estuary Locations

1. Mouth of the Avon River

Sea run trout will move into the channel during spring. At this time of year, trout will be chasing the prolific schools of silveries and whitebait. Last year an eight-pound sea run was caught next to the Avon River’s mouth into the estuary.

Feathered lures such as the Black Prince fished with split shot or a range of spinners such as Tasmanian Devils, and red/silver Veltics could entice that big sea-run brown trout moving through.

2. Heathcote Channel

Runs next to the causeway. This well-defined channel can be seen at low tide. Use live sandworms as bait on a running sinker, with a size 8-12 hook fished at low tide for flounders.

During the low tide, flounders are concentrated in the channel. The bait must be lying on the bottom. Flounders are regularly taken by people drag-netting in the Heathcote channel. So the challenge is there if you want to target flounders on rod and line.

3. McCormacks Bay

Channel and nearby mudflats. The mudflats next to McCormacks Bay are covered with dense beds of sea lettuce and provide a great place to catch yellow-eyed mullet on high spring tides. Fish the shallow mudflats with a small hook baited with sandworms to catch mullet. Occasionally a kahawai will break the surface and scatter the schools of mullet.

A small silver spinner can be used to entice the kahawai if they are about. The deep channels in McCormacks Bay are occasionally full of mullet. Reef fish such as banded wrasse are attracted by the dense bed of mussels in the McCormacks Bay Channel so keep an open mind.

4. Redcliffs Wall

Another easily accessible roadside fishing location. The deep channel quickly shelves away and reaches eight metres depth in places. A wide range of habitats are found in the channel, with sand in the deeper parts of the channel and rocks covered with mussels along the edge.

Large schools of blue moki entered this reefy part of the estuary as recently as the early 1970s, but appear now as only occasional visitors in the estuary. Blue moki appear to have been depleted in local waters over recent years.

Paddle crabs feed on tuatua beds well out in the sandy channel next to the Redcliffs Wall.

Occasionally rig sharks will move into the estuary to feed on the paddle crabs. But rig, like blue moki, appear to have become depleted in local waters over the last ten years. Rig are extremely selective feeders and paddle crab makes an ideal bait.

Large schools of kahawai occasionally enter this part of the estuary. Large flocks of white-fronted terns working over schools of bait fish are a good indication of the presence of kahawai in the estuary during summer.

Juvenile kahawai are prolific in the outer estuary and will readily hit a wide range of baits, providing great fun for the kids.

Red cod move into Redcliffs and Moncks Bay with the tide to feed on the bountiful crabs.

5. Shag Rock

Shag Rock – the Māori name is Rapanui – collapsed during the Christchurch earthquake in February 2011. Best fished on the slack water at either end of the tide’. During the ebb and flood of the tide strong currents form and will foul your fishing gear with sea lettuce.

Shag Rock is well known for the schools of red cod which move through the shallow sandy channel. Oily baits such as yellow-eyed mullet are ideal. Shag Rock is a popular location for catching mullet. Baits such as mussels are also effective and locally available. Mussel baits need to be tied onto the hook with cotton to prevent pickers from stripping away the bait.

The red cod prefer to enter the estuary and feed during low light so early morning and the evening are the best times to fish for red cod. The surf at the entrance of the channel at Shag Rock is a great spot for kahawai fishing over the summer.

Further off the coast out in the Sumner Bar thresher sharks occur over summer. The threshers are probably attracted by the schools of kahawai offshore.

6. Brighton Spit Tip

A good location to fish on the low tide when the deep sandy channels are easily accessible. Flatfish, especially soles, are common over the sand.

The best baits to use are yabbies or sandworms. Cockle beds also attract fish into the area.

More interesting info on the estuary is on Wikipedia.

Food gathering practices at the Avon-Heathcote Estuary Ihutai Canterbury Aotearoa/New Zealand pdf