The regularity of mated or otherwise fully to near-fully mature male and female Architeuthis off these two areas, Hokitika Canyon and Banks Peninsula, suggests that these are breeding grounds, and that the adult squid have migrated into them. Unless pheromones are involved (squid perfumes), both male and female (or male/male and female/female) probably just bump into each other in the dark. After a moment of panic, sixteen arms and four tentacles entangle and the giants go beak to beak.
The relatively long terminal organ (penis) of a mature male is almost the length of its mantle, from which it projects freely, through the funnel, for a considerable portion of the organ's length. Species with such long organs presumably use them directly to implant spermatophores hydraulically into the female, and as a rule lack modification of either ventral arm (hectocotylus) for spermatophore transfer. Architeuthis lacks a hectocotylus.
Architeuthis sperm injection
His metre+-long penis presumably injects numerous spermatophores directly into the female's arms (Fig. 4, left). The two animals then separate, the male swimming away, probably a bit beat up (possibly having lost parts of his arms and tentacles in the violent struggle; see cannibalism thread), but none the wiser likely repeats this affair with another female (should the opportunity arise). His spermatophores remain embedded in each female's arms - possibly burrowing even deeper into their flesh.
Copulation is likely to accelerate maturity of the female. Eggs soon funnel from her large, terminally positioned ovary into long, convoluted proximal oviducts (Fig. 5). From here they advance to the oviducal glands, structures that secrete to the egg chemicals that, amongst other things, initiate sperm activation and attraction. Passing from these glands the eggs would discharge from the distal oviduct, possibly in strings, directly into the female mantle cavity. The nidamental glands (Fig. 6) would then secrete vast amounts of jelly, probably almost entirely filling her mantle cavity. This jelly binds with discharging eggs, and like a cement mixer, her mantle probably rhythmically contracts and relaxes, thoroughly mixing them. Shortly afterwards this mass of jelly and egg would be extruded through her funnel, and a sphere-like egg mass of ~half-a-metre in diameter would be released. This mass would then be taken into her arms where she would cradle it as it absorbed seawater and increases in size (possibly to two-or-so metres diameter)
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