NATURE NOTES.

New Zealand Herald, Volume LXIX, Issue 21141, 26 March 1932, Page 1 (Supplement)

NATURE NOTES.

THE BITER GETS BITTEN.

B? J. DRUMMOND, F.L.S., F.Z.S.

A bee struggling in a spider's weh attracted the attention of Mr. J. Proctor, North-east, Harbour, Dunedin. He watched in order to see what would happen. Coming down the web, the spider stopped about 2in. from the bee. Jfc waited for perhaps three minutes, as if in doubt. Deciding to "chance it," it rushed at tho bee. The spider, apparently, tried to keep, the bee's back toward it. After a struggle that continued for a few seconds, the bee, whirling, delivered a thrust with its sting. This caused the spicier to retreat a few inches. It did not advance again and tho bee soon afterwards escaped. A few minutes later the spider crawled feebly away. "It may have been stung," Mr. Proctor states, "but it has made a good recovery, and, at the time of writing, is getting quite fat." The relationship of wasps to spiders is known to almost everybody. Apart from these hereditary, implacable and deadly enemies, spiders often fail to have it all their own way. even with defenceless flies, which, proverbially, walk into the spiders' parlours and do not come out alive. Some species of flies—this refers to the whole order of flies, the Diptera, not to common house-flies only—prey upon spiders. Two flies were seen to seize garden spiders in the centre of the spiders' webs. The flies'calmly sat in the webs while they devoured the owners. The commotion in one web attracted the attention of a male spider. It ran down to see what was happening, but hastily retreated. Dadddy-long-legs, which belong to the order of the flies, have been seen hanging by theiT front legs on the stay-lines of garden spiders' webs like washing hung out to dry on a clothes line. Mosquitoes sometimes make the same use of webs, evidently finding them convenient restingplaces. When disturbed, the flies take to flight. Dung flies sometimes have the audacity to sit. in garden spiders' webs and suck the juices of insects caught in the webs and wrapped up by the owners. A wasp dragged a struggling fly out of a web before the spider had time to seize the captive. A large insect was seen carefully examining small flies caught in a large web. It gave each captive a slight tug and finally pulled one out forcibly and flew home with it. Students of spiders have been puzzled to account for the habits of some flies that sit on spiders' backs. One explanation is that riding-flies do this in order to get a lift to a suitable substance in which to lay their eggs. Another explanation is that the flies are parasites on the spiders. A spider was found sharing its meal off a dead bee with several flies. This seems to show that some riding-flies at least sit on spiders' backs, wait there until a spider catches an insect and then dines with the spider. There is evidence of parasitism in grubs of flies emerging from a spider's body in order to eater the chrysalis stage of life.. It may be concluded that in this case a riding-fly laid its eggs in the spider's body and that the young grubs, on batching, fed on the spider. Innumerable eggs of never hatch. Birds see to this by using the silken cradles for lining and draping the nests. Ichneumon flies lay their eggs in the warm cocoons. When the young ichneumon hatch they feed on the spiders' eggs, every spider's egg being destroyed. During growth a spider moults eight or nine times. These moults are described by Mr. C. Warburton, one of the deepest students of spiders, as very dangerous to spiders, quite as dangerous as measles are to young children. For some time before a moult, Mr. Warburton states, a spider takes no food. It becomes inert and Apparently dead. The old s kin splits. The spider struggles out, soft and pale. It leaves behind not only its outer skin, but also the lining of most of its alimentary canal and of its breathing tubes. If it fails to extricate itself it dies. Often it emerges with the loss of a limb. This reappears at the following moult, but is reduced in size. So severe is the strain of a moult that the spider must v go into retreat till its skin has hardened and its strength has returned. Mr. Proctor sent a very beautiful little Epeira, its back embellished with gold and red, its limbs coppery, on , March 1. Twenty days later it was so lively that it almost sprang out of the box in which it was imprisoned. Several flies placed in the box doubtless were acceptable food; but spiders fast for an amazing time and retain their vitality. This is an offset to the dangers that come against them at every turn. It is not surprising that they are alert, ferocious and ruthless. Tho famous wry-billed plover, the only bird known with its bill turned to one side, was seen by Mr. E. T. Frost at Doubtless Bay several weeks ago. He saw about twelve individuals in a flock. They were so friendly that he went within a few yards of them. As he states, this species, known to Maoris as ngutuparore, is one of this Dominion's ornithological curiosities. Efforts to explain the unique form of the bill—it always is bent to the right—on utilitarian principles arc not satisfactory. This plover, in small flocks. \ isits mudflats and sandflats on the coast and shingly riverbeds inland, feeding on creatures that live in inter-tidal areas. As far as knowledge goes, it could search for food as easily with a straight bill as with a wry one. Mr. Frost saw the wry-bills associating with young banded dotterels, the two sashes worn across their breasts just beginning to show. Not unusually, wry-bills associate with godwits, most, famous of all the shore-birds. The godwits are spending the late summer months in New Zealand. They soon will leavo for their Siberian homes. The wry-bills also are migrants, but they are not voyagers, staying in New' Zealand all their lives and migrating merely from the South Island to the North Island. They nest and rear their families in tho South Island only, laying their pale, green eggs, marked with small black lines and blotches, among the stones and shingle on riverbeds. The wry-bill was discovered by Q.uoy and Gaimard, zoologists on the French exploring vessel Astrolabe, when it visited New Zealand 104 years ago. They found it in small flocks on mud-flats in the Hauraki Gulf, Its breeding and feeding habits were first observed by Mr. T. H. Potts, who lived at Governor's Bay, Lyttelton Harbour, and gnvo much time to studying the plant and animal lif» of New Zealand.