A Study of the Marine Spiny Crayfish Jasus lalandii (Milne-Edwards) Including Accounts of Autotomy and Autospasy
Fishing Methods and Locality of Fishing
Fishing Methods and Locality of Fishing
The specimens examined on the commercial boats were trapped in the common type of pot—namely, a beehive-shaped basket made of supplejack vines with a tapered opening at the top. The height of the pot is about 14 inches, the breadth about 27 inches, and the distance between the horizontal rings of the basket one inch to two inches. The diameter of the external mouth of the funnel is 12 inches, and of the internal mouth seven inches. The length of the funnel is six inches. These measurements are approximate, as no two pots are identical. The pot is weighted and a hauling rope is attached near the base so that it is hauled up on its side. The other end of the rope is attached to a series of cork floats which marks the position of the set pot.
The most common bait used is fish heads, since they are effective and are easily obtained from other fishing boats. Paua (Haliotis iris) is considered to give better results, but is harder to obtain and is therefore not used extensively.
The number of pots used depends on the size of the boat, and varies, as pots are lost from time to time. This variation has been noted in order to find the variation in the catch per pot per day. The commonest boats carry two men and page 5 employ 18–20 pots. Fig. 1 shows the average number of sacks taken by 20 pots on an "average" day each month. (A sack contains approximately 100 lb.)
All of the specimens examined on the commercial boats were caught along the rocky coastline from Oteronga Bay to the mouth of the Orongorongo River between 50 and 800 yards off shore in depths varying between 2.7 and 14.2 fathoms. The areas fished each month are given below (see Fig. 2).
January | Oteronga Bay to Sinclair Head |
February | Oteronga Bay to Sinclair Head |
March | Sinclair Head |
April | No fishing due to off-season |
May | Ohiro Bay |
June | Sinclair Head to Dorset Point |
July | Ohiro Bay to Pencarrow Head |
August | Moa Point to Fitzroy Bay |
September | Karori Rock to Island Bay |
October | Near Island Bay |
November | Moa Point to Dorset Point |
December | Breaker Bay to Fitzroy Bay |
The pots were cleared and rebaited every morning (weather permitting) and, at about weekly intervals, were moved to different parts of these areas.
In June, July, and August, 1948, experimental fishing was carried out at Moa Point, mainly to supply specimens for tagging and laboratory work. A ten-foot dinghy and four spot-welded No. 6 gauge wire pots of one-inch mesh were used. Fish-heads were used for bait, and a total of 171 crayfish were caught. The pots were set around Moa Point within 100 yards off shore. They were lifted on each occasion twenty-four hours after they were set.