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Tanon Straits between Negros and Cebu, Tinaogan Reef, north of Bindoy, Negros Oriental

9.8° N
123.1667° E

100.0 - 300.0 m

Sept. 11, 1975

bobo traps

R/V Alpha Helix

local fishermen | Ann Hurley | party

Ann Hurley

dry

dry

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Details from email from Ann Hurley to Bill Newman, 11/12/98 11:32 am, subject: Nautilus; printed version with specimen and digital photo taken, 2022-04-21. "...it would have been collected during a 1975 cruise of the Alpha Helix in the Tanon straits between the islands of Negros and Cebu in the Philippine Republic. Most of the collecting was done in the vicinity of Bindoy, Negros Oriental. The cruise is described in J. Exp. Zoology, 205, 1978: 1-4. I'm not sure how deep the animals were caught, but it was likely below 100 m. They were caught in traps by the local fishermen." Expedition members: Norine Haven, John Arnold, Lois Arnold, George Bourne, Pedro Gonzales, Peter Hartline, Peter Hochachka, Ann Hurley, Kjell Johansen, G. David Lange, Arthur Martin, and James Redmond. Description in same issue of J. Exp. Zoology, 1978: Ward and Martin (pp. 5-12): "Nautilus macromphalus were captured in New Caledonia in cubical wood and wire traps about 1 m on a side, baited with fresh fish or crab, and attached by line to a surface buoy. Traps were placed outside the barrier reef in water 50 to 100 m deep for one to three days. Scuba was used to capture six animals in shallow depths at night. The animals [N. pompilius Linne] observed in the Philippines were captured with traps similar to those used in New Caledonia."; Hurley, Lange, and Hartline (pp. 37-44): "Animals [Nautilus pompilius] for these experiments were obtained in the Tanon Straits off Negros Oriental, The Republic of the Philippines. They were caught at depths ranging from 100 to 300 m. Haven ('72) describes this locale in detail and discusses the procedure for trapping the animals." NSF grants OFS74-01830 and OCE74-02888. Details in Haven, 1972 (https://www.biodiversitylibrary.org/part/93561): "At present, 4 fishermen from Negros Oriental set traps near Tinaogan Reef, north of Bindoy (Figure 1) (9 48' N, 123 10'E). Bobos -- traditional bamboo fish traps similar to those described by Dean (1901) -- are baited with fresh chicken, fish or pork and set on the bottom, from 60 to 240 m deep. The traps are pulled each morning...The bobos used by the nautilus fishermen are set near coral reef areas where the bottom drops from 40 m to approximately 240 m within a mile from shore. The Tanon Strait deepens to 400-600 m a short distance beyond....Fishermen in the area report the bottom environment on the north side of Tinaogan Reef to be rocks and coral heads to about 90 m, and mud to limits of their trapping there (approximately 150 m). The bottoms of traps brought up sometimes drip a grey mud. In experimental trapping at various depths, no Nautilus pompilius were ever captured shallower than 58 m." Details from letter (undated) from Ann Hurley to Bill Newman: "According to my lab notes, we were catching animals from about 11 Oct. 1975 to 11 Nov. 1975. If the number on the animal was <=52, it was caught on or before 19 Oct. Similarly <=112, on or before 25 Oct; <210 on or before Nov. 8." Shell 223 inferred to be collected between Nov 9-11, 1975.