Big Landlocked Salmon from Lake Hawea, Otago

Landlocked salmon don’t usually grow very large. Only limited information is available on land-locked stocks of quinnat (or chinook) salmon in New Zealand. So when Dick Marquand phoned from Cromwell to say that he had the frame of the largest landlocked salmon he had ever seen, we were very interested. The fish had been caught by a Mrs P Linton in Lake Hawea on back on 3 December 1995. Weighing 3.05 kg (6.75 lb) and measuring 60.5 cm with a condition factor of 138, it was certainly a memorable fish.

The typical weight of landlocked salmon is usually no more than about 1.5 kg, although there are reports of apparently land­locked specimens from Lake Coleridge of up to 4 kg in the early 1930s, with occasional fish this size taken since.

Examining the scales and otoliths (ear bones) indicated the fish was 3.5 years old, which means it was no older than the usual oldest fish found among landlocked stocks of salmon. What was very noticeable from the width of the rings on the otoliths was that the fish had made very fast growth over the preceding 6 months.

This implies that some very good source of food became available during this time. The source became clear when examining the stomach which contained one salmon, about 20cm long, and the vertebrae from probably another one. It seems like that fish had grown large enough by early 1995 to begin feeding on the very abundant smaller salmon that were present in the lake throughout the year.

Although there is another verified account of a large 3.2 kg salmon caught in Lake Coleridge in November 1988 (which also contained one 15-18 cm salmon in its stomach), it is possi­ble it was a sea-run salmon – although it is difficult for sea-run fish to get into this lake. Thus the fish caught in Lake Hawea appears to be the largest on record for that lake, and the first record of a salmon of this size which has definitely been land-locked for its entire life.