07 December 2018

Bell Air postscript

Thanks to Darryn who wrote to me during the week following the updating of the Bell Air post... see : http://3rdlevelnz.blogspot.com/2010/02/bell-air-remembered.html

Darryn writes,

A great revision to your Bell Air profile!

I grew up in Whakatane and spent many hours with Graeme or Red Barker fish-spotting or bludging rides on the Auckland service in either PAT or LLA.  I pop by and see Graeme and Pat whenever I’m back home (hasn’t been for a couple of years now but they were both very well last time I dropped in).

I’ve attached a photo of PAT on the ground at Whakatane probably late 70’s.  You’ll see the flag flying on the tower - Flight Service was still active then!

Thanks for your fantastic blog!

Best wishes

Darryn Morgan

This is Darryn's photo... but later than late 1970s...

This is my photo of PAT in August 1981

And in May 1988 without the tail logo... I also have it like this in 1984. My question is, wht was the tail logo removed??? Any thoughts anyone??? 

In researching the expanded post on Bell Air I found this paper Graeme Bell presented on fish spotting...

Aerial Spotting for Pelagic Fishes 
My company, which was established in 1968, uses three aircraft in air charter and aerial spotting work. These are a Piper Aztec twin, a Cessna Cardinal 177B, and a Cessna 172, the last two being single-engined. We are based in Whakatane and undertake charters to all parts of New Zealand. My interest in aerial spotting for surface schools of fish was aroused while flying charters for the Marine Department during the 1967-68 summer. At that time Mr Don York (now ol the Ministry of Agriculture and Fisheries) was studying tuna in the Bay ol Plenty and it was he who provided me with much early tuition on school locarion, estimation of school size, and species identification. Since then I have carried out fish spotting along most of the New Zealand coastline. This has been in conjunction with various research projects (for example, Roberts 1971), the activities of research and charter vessels (Espirito Santo 1970-71, W  J Scott 1970-71, Paramount 1973-75, James Cook 1975-76, Michelangelo, Kerri M, and South Pacific 1975-76), Government surveys (see Eggleston 1975, 1976. Habib 1975, 1976, Robertson 1975, James 1976) and the fishing activities of New Zealand vessels such as Lindberg, Marine Countess, and the Bay of Plenty small-boat fleet. Contact is made with vessels through an HF Double Side Band radio set on frequencies 2045, 2456, and 2638 kHz. I also monitor the Marine Distress frequency 2182 and the Police frequency 5680. Locating pelagic species from the air is largely a matter of experience. Schools of fish tend to form "smudges" on the surface which are characteristic for the different species. The action of schools swimming along just below the surface tends to ripple the surface water and cause these smudges. In moderate to rough seas this action tends to dampen wave action and so schools in these conditions are seen as "flat spots" or small areas of relatively calm water. Feeding schools are usually more obvious. Often accompanied by sea birds, these schools tend to break the surface o[the sea in their feeding movements, at times creating a foaming appearance. Finding particular species is also a matter of experience. For example, certain species are regularly found in particular areas at certain times of the year: trevally - Astrolabe Reef, Penguin Shoal, Three Kings Islands; kahawai - Graham, Pandora, and Ariel Banks; blue maomao - White Island. Cape Breg; jack mackerel - Penguin Shoal, Waikawa Point; English mackerel - North Cape, Graham Bank; skipjack - East Cape to North Cape on the east coast of the North Island, between the 30- and 100-fathom (55- and 183m) depth contours. Species identification from the air is based mainly on school colour. swimming, and schooling behaviour. Jack mackerel schools are muddy-brown, English mackerel steel-blue, blue maomao light sky-blue, trevally and kahawai green-yellow, albacore and bluefin black, yellowfin black with yellow flashes, skipjack purple-blue with silver flashes, anchovy silver, and pilchard green with silver flashes. Slow swimmers are jack mackere l, kahawai, blue maomao, anchovies, and pilchards; medium to fast swimmers are English mackerel, trevally, and the tunas. Species can be confused in situations where the light is inadequate or where the sea is moderate to rough. Trevally and kahawai both have a sinuous body action during tail movement, but this action is more accentuated in kahawai, and trevally tend to school closer together. English mackerel and skipjack can be confused. In certain lights they have a similar colour and when disturbed they sound in a similar manner. However, skipjack are generally larger fish with distinctly bullet-shaped bodies. Albacore and bluefin tuna are often confused. However, if the fish are observed long enough, the large pectoral fins of albacore become apparent. If the fish are particularly large, they are probably bluefin, which grow to over 300 lb (136 kg). Anchovy and pilchard schools often look the same, but they can be distinguished when they sound in response to aircraft noise. On a low pass you never see individual anchovies, but you will see pilchards. If sea birds accompany frsh schools, gulls and terns are usually associated with kahawai and mackerel; petrels, shearwaters, and gannets usually accompany tuna. I have tested many of my identifications through radio contact with fishing vessels and as a result have built up a number of other criteria. School size is usually estimated according to the species of fish. Density, surface area. and depth of school are taken into account. Often a school will cover a large surface area and at first glance appear to contain a large quantity of fish. However, these schools almost as often have no depth (no colour) or any density, as the individual distances between fish are large. My confidence in estimating school size has been built up by providing vessels such as Lindberg, Marine Countess, and the chartered seiners with estimates of schools which they have then caught and weighed. Much of my aerial spotting work now revolves around fishing and directing vessels to schools of suitable size, taking into account sea conditions, and vessel holding capacity and catching ability. This direction is often critical. Particularly for the smaller seiners, as catching a school which is too large in marginal sea conditions can be disastrous. I would like to conclude this paper with some points on the cost-effectiveness of aerial surveys. The effective spotting distance either side of an aircraft flying at an altitude of 500 to 1000 ft is 3 miles. Flying in my Piper Aztec at 155 knots, I can survey 930 square miles in an hour at a cost of $95.00, or about 10 cents per square mile. In the Cessna Cardinal, which flies at 110 knots, the figures are 660 square miles an hour at a cost of $45.00, or about 7 cents per square mile, and in the Cessna 172 flying at 95knots,570square miles at $38.00, or 6.7 cents per square mile. Apart from the benefits of having an aircraft on hand to locate, identify, and estimate size of schools, and provide information necessary for successful fishing operations, the aeroplane is unsurpassed in the business of surveying large areas of water for pelagic fish species quickly and at reasonable cost.

Source : G R Bell, Aerial Spotting for Pelagic Fishes, in Proceedings of the Skipjack Tuna Conference, July 1976, Fisheries Research Division of the Ministry of Agriculture and Fisheries, Occasional Publication No. 11, 1976 

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