Jump to content

The Kea: a New Zealand problem/Chapter 13

From Wikisource

CHAPTER XIII.


DISTRIBUTION.


From the dark gorge where burns the morning star,
I hear the glacier river rattling on
And sweeping o’er his ice-ploughed shingle-bar,
While wood-owls shout in sombre unison.
And fluttering southern dancers glide and go;
And black swans’ airy trumpets wildly, sweetly blow.

—Anne Glenny Wilson.

The area of the Kea’s distribution is continuous, but very limited. It is confined solely to the mountain country of the South Island of New Zealand, which extends for 400 miles in one direction and 80 miles in the other, making altogther an area of some 40,000 square miles.

Wherever there is mountainous country in the South Island, with the exception of the Kaikoura Mountains in the North East, the Kea can be found.

It was first discovered by Mr. W. Mantell in 1856 in the Murihuku district, which embraces practically all Southland. It was a rara avis, and some thought that it was confined to Southland. However, as soon as men pierced the mountain fastnesses that run up the west coast of the island, its distribution was found to be much wider. A few years after its discovery others were found, not only in Southland and Otago, but in Canterbury as far north as the Rangitata Gorge, about 200 miles north from where it was first seen. In 1859 Sir Julius von Haast saw it in the Mount Cook region, and a year later Sir W. Buller found it in the Rangitata Gorge.

As early as 1862 Sir James Hector noticed it in most of the snow mountains of Otago, during his Geological Survey of that province, and in the same year Sir Julius von Haast saw one on the Godley Glacier. In 1865 Sir Julius found it a long way above its supposed limit,—around Browning’s Pass at the source of the Wilberforce River; and two years later he saw it still further north, near Arthur’s Pass on the West Coast road.

In 1868 Keas had become common around the Lakes which lie on the borderline of Otago and Canterbury, and ten years later they had increased all round the spot where they were first found, for Sir W. Buller speaks of them as being plentiful in Southland.

In 1881 they were again seen at Arthur’s Pass, for Dr. L. Cockayne (in a communication to me) states that his brother-in-law, Mr. A. Blakely, shot one there at that date.

A year later, in 1882, Mr. W. Potts reported that Keas were known at Grassmere on the West Coast road, and in Lochinvar Station, North Canterbury, and at the head waters of the Esk and Hurunui, that is, about forty miles still further north of Arthur’s Pass their then supposed northernmost limit.

In view of all these facts it is surprising to find Sir W. Buller, in 1883, quoting a letter from a Mr. Shrimpton to the effect that the Keas’ area of distribution did not extend north of the Rakaia River. This is the more striking, because both Dr. Haast and Mr. Potts had already published records of Keas seen northward of that limit. The former found them at Arthur’s Pass, 40 miles north of the Rakaia, in 1867; and the latter tells of their being seen at Hurunui, another 40 miles north of Arthur’s Pass.

Later, in 1888, Mr. W. W. Smith, in a published article, says that Keas had, during the previous three years, just reached the ranges above the Otira Gorge. However, like Sir W. Buller, he had evidently not seen the report of Dr. Haast as to their being seen years before at Arthur’s Pass, which is as far north as the Otira Gorge.

It has been freely stated by writers on the Kea that, since its discovery in Southland, the bird has gradually migrated northward through the Otago and Canterbury provinces. This suggestion has not only been published, but has been almost universally adopted as true. This wide-spread acceptance is unfortunate; for, on looking up all the available records, I find that the evidence does not support the statement. The evidence rather indicates that, whenever and wherever men have penetrated the mountainous country of the three lower provinces of the South Island, Keas have been found in the parts explored. It was because the Otago and Southland mountains were explored first, and the Canterbury mountains a little later, that the idea of the northern migration was suggested, and very likely, if Dr. Haast and Sir James Hector had explored the Canterbury alpine region first, the alleged migration might have had its direction reversed.

Even if we take the dates and places of the Kea’s discovery, the facts do not uphold the theory. In 1856 Mr. W. Mantell found the Kea in Southland,—the exact spot is not recorded. Then, instead of finding it a few miles further north in Otago, Dr. Haast discovered it three years later at Mt. Cook in Canterbury, about two hundred miles further north, thus missing the large Otago province which lies between. It was not till three years later that Sir James Hector reported it to be among the snow mountains of the intervening province.

In the same year Dr. Haast saw it at Browning’s Pass, about 80 miles still further north, and in 1867 it was known at the Lochinvar Station, sixty miles further north again of Browning’s Pass. We have no record of the Kea being found further north than the Lochinvar Station until 1882. This is very likely due to the fact that no scientific man explored the country. If one did, he left no available records.

It will thus be seen that, instead of the Kea’s area of distribution being increased a few miles further north year by year, as would have been the case had the birds travelled north, the birds were found at different places, sometimes 200 miles north of their previous location, while they were not found in the intervening country until many years afterwards.

It is also very unlikely that, the moment the birds were discovered, they made a rush northward, so that in eleven years they had migrated 300 miles from their old homes.

There are two pieces of evidence entirely against this unlikely proceedure.

First, if the Keas had migrated, then they should have become rare in Otago and Southland; but in fact they were not very plentiful in the south until after 1868, and by this time the Kea was recorded at Lochinvar, some three hundred miles further north.

Second, the reason given for the Kea’s migration is that the systematic slaughter in the early days drove them north; but the whole idea falls to the ground when we remember that, in 1867, a year before the bird was even suspected of sheep killing, and so a year before the slaughter of the bird began, the Kea was recorded from the Lochinvar district, that is, the very country into which it was alleged to have been driven by the aforesaid systematic slaughter.

There is however, a lot of sound evidence to show that the Keas’ area of distribution is widening. This widening is due, as far as I can ascertain, to the great increase in their numbers; for, though their numbers have been thinned by forty years of continuous slaughter, they are still numerous in many parts.

It was noticed that, soon after the birds began to kill sheep and eat them, their numbers increased so that where they had been seen in tens they could be seen in fifties. Many sheep owners put this down to the plentiful supply of food obtained from the dead animals.

This would appear at first sight to show that all Keas killed sheep; but I have already, I hope, made clear that only a comparative few do the killing, though the rest may join in the feast.

This increase has naturally caused the Keas’ area of distribution to expand; and now, instead of confining themselves to the main ranges, they come down even as far as the foot hills on the east and the sea coast on the west. The latter limit is supported by the fact that they have been seen at Koiterangi, near Hokitika, and at Mahitahi, near Bruce Bay; while in June of 1906 Captain Bollons, of the Government Steamer, “Hinemoa,” told me that he saw one flying along the beach at Bruce Bay itself.

To the east they have come down to the edge of the plains, and south almost to the coast line. The only direction in which the birds can now extend is north into Nelson and Marlborough; and, though the Keas’ northernmost limit remained at the head waters of the Esk and Hurunui Rivers for about forty years after their discovery, there has been during the last few years a spreading into these two northern provinces. The stations around Hanmer have been troubled with Keas for some years, and in 1903 Mr. Edward Kidson, while climbing Mt. Robert near Lake Roto-iti, Nelson, saw one at close quarters. This spot is about 40 miles south-west of Nelson city and 40 miles north of Hanmer. Mr H. M. Bryant, who was accompanying Mr. Kidson at the time and has done a lot of mountaineering in the Nelson province, states that he had never before seen one in that district; while the late owner of the station at Mt. Robert told him that it was the first time that a Kea had been seen on his run.

Through the kindness of Mr. G. R. Kidson, I am able to record two other instances in the Nelson province. In 1904 a Kea was caught by Mr. A. G. Hammond at Appleby, only thirteen miles south-west of Nelson city, and in the same year Mr. T. S. Rowling caught one at Riwaka, a few miles north of Motueka, about 50 miles north-west of Nelson and 95 miles north of Hanmer.

This is at present the northernmost limit of the Kea’s area of distribution, which may be defined on the north as reaching the shores of Cook Strait.

Through the aid of Mr. T. E. Currie, I can now publish reports of the Kea’s presence in the Marlborough province, where before it was practically unknown, showing that in addition to travelling up north-west through Nelson, they are also travelling up north-east through Marlborough.

In January, 1906, one was found at the head of the Waihopai River, at a place known as the Glazebrook Whare.

Again, in May, 1906, one was seen on the Tarndale Station, about halfway up the Saxton River, some miles north of the homestead.

Another correspondent reports that he has seen one thirty miles only from Blenheim, the capital of the province.

Now that Keas have reached the north coast of the South Island, one wonders if the Cook Strait will prove a sufficient barrier to prevent them from flying over to the North Island and spreading there.

The two islands are only 15 miles apart at their nearest points, and on a clear day the opposite coast can easily be seen.

This northern extension of recent years does not, I consider, in any way support the old idea that the birds migrated northward for a decade or so after their discovery.

They were known at the Lochinvar Station about 1866-7, and since then they have practically not made any further advance until 1900; but at the present time they are certainly spreading northward.

The migration may be due to the increased numbers, or perhaps to the incessant slaughter which has been going on for some years.

What really started the northern migration theory was knowledge of the fact that, though the Keas themselves never migrated northward in the early days, yet the habit of sheep-killing has extended from Otago northward to Nelson. No one thought of recording the Keas’ presence as long as they did no harm, but as soon as they began to harass the flocks reports were sent to the daily papers.

As the habit gradually spread northward many jumped to the conclusion that the birds had just arrived, whereas in many instances we know that the birds were on some of the stations years before they commenced to kill.

For instance, at Browning’s Pass the Keas were seen in 1865, but no cases of sheep-killing were known until 1886.

The first instance recorded of sheep-killing was in 1868 in the south near Lake Wanaka; and thence the killing has spread south to Lake Wakatipu and north to the Amuri district, including Hanmer. About 1880 the bird’s depredations were recorded at the lakes south of Canterbury, and by 1886, after passing north through the Peel Forest and the Ashburton Gorge, the Kea had commenced to kill sheep around Mt. Torlesse. Since then it has slowly extended north to the stations in the Amuri District, and so badly affected were they that in 1906 a meeting of runholders was held in Culverden to try to abate the nuisance.

So far I have no records of sheep-killing in Marlborough and North Nelson, though the Keas are now found there.

In Westland also the Keas have spread, for in 1906 Mr. Condon, of Bruce Bay, South Westland, for the first time had some sheep killed by Keas.

Two wing bones and a lower mandible of a Kea found in the Chatham Islands and now in Canterbury Museum.

Bones of Kea: Found in Chatham Islands.

The fact that no fossils of Keas have been found in the North Island of New Zealand seems to indicate that the birds never extended further than the South Island; but, while in the Museum, Christchurch, I unexpectedly came across two wing bones and a lower mandible of a Kea, obtained from the Chatham Islands. These interesting specimens were presented to the Museum by Mr. J. J. Fougere, of Te One, on the main island, and were identified by the late Capt. F. W. Hutton. These, with some more Keas’ bones and other sub-fossils, were found in some drifting sand-hills at Petre Bay, by Mr. Fougere, in 1897. In a letter he states: “I do not think the Kea or Kaka were ever numerous in the Chatham Islands, as their remains are rare in comparison with the other fossil avi-fauna.”

From the number of fossils already discovered, there seems to have been a much larger avi-fauna on the islands than at present.

This is supported by a pamphlet written by Dr. Arthur Dendy, (then Professor of Biology, Canterbury College), who visited these islands in 1901.

He says:—“All who have studied the question are agreed that the fauna and flora of the Chatham Islands are simply isolated detachments of those of New Zealand, although the striking differences which we have had occasion to notice imply a long period of isolation. This view of the case requires us to believe that the islands, though now separated by 400 miles of open ocean, were at one time either actually connected with the New Zealand mainland, or, at any rate, much more nearly so than at the present day, a belief which is strongly supported by the fact that the sea between New Zealand and the Chathams is comparatively shallow, only from 500 to 1000 metres in depth, while further to the east it sinks at once to 4,500 metres (Diels). In the Upper Pliocene period it is probable that the area of New Zealand was greatly extended so as to embrace, for example, Chatham Islands in the east, Lord Howe Island in the north-west, Auckland and Campbell Islands in the south. . . . . . This condition is supposed to have lasted on into the Pleistocene times, and to have been followed by another depression, which left the islands very much in their present condition. The former land connection thus roughly sketched out, together with the ocean current already referred to, would be quite sufficient to account for the great resemblance between the fauna and flora of the Chatham Islands and those of New Zealand.”

The geology of the islands seems to indicate that they once formed part of the large area, as is shown by the presence of schists and similar rocks, while the finding of limestone seems to point to a depression at a later period.

The land thus seems to have been elevated and again depressed, leaving it very much in its present condition.

This closer connection between the two groups of islands may explain the presence of Kea fossils on the Chathams.

This theory, however, only adds mystery to the strange fact that no Keas or Kea-fossils have ever been found in the North Island, situated only 15 miles away.

The Kea’s extinction.

As early as 1888, Sir W. Buller says that he is certain that these interesting birds would soon be extinct, but in spite of the thousands that have been killed they are still common in the mountainous country of the South Island. No doubt the almost inaccessible position of their nests, and the rough nature of the country in which they live, are responsible for their preservation.

When harassed they often retreat to the most inaccessible fastnesses of the Alps. Here they are practically safe, for this exceedingly rough country can never be of much use except for scenic purposes. It is, therefore, doubtful if the Kea will become extinct for many years to come.

If, however, closer settlement of the land, accompanied by the destruction of the forest and the systematic slaughter now going on, should threaten to exterminate the Keas, I would suggest that, in order to prevent these interesting birds from becoming absolutely lost to the scientific world, a number of them should be placed on one of the outlying islands, where they could live and flourish without doing injury to any one. The most suitable islands, as far as I can ascertain, are the Aucklands, which lie 190 miles south-by-west from the most southerly point of Stewart Island. There would be very little chance of the birds returning to the mainland; and though the hills rise to a height of about 2,000ft. only, there seems to be enough forest and high country to make a very satisfactory reserve for these interesting parrots.

Attacking other animals.

Though the sheep are favourite objects of the Kea’s attack, it does not seem to confine itself to them, for several instances are reported where horses, dogs and rabbits have been mauled. I do not consider that these attacks are really made to procure food, but rather for fun and mischief.

One correspondent gives the following account of an attack upon a horse:—“The pack-horse was tethered on a piece of flat ground about ten chains from the camp. After we had tea, I strolled over to where there was a large flock of Keas on a little knoll above the pack-horse. This would be about an hour before dusk. One or two flew down on to the horse’s back. He was an old, stiff-built cobby horse of very sluggish nature. He took no notice of the Keas when they flew off and on his back for some time, giving him an occasional peck. At last an old fellow perched on his back and started operations in a most serious manner. He soon had the old horse showing more life than he had ever done before; in fact, before he got the Kea dislodged, he was almost mad. When I got down to him, he was in a heavy sweat, and the blood was trickling slightly over his loins. On examination I found a nasty wound that took a long time to heal, as it became very dirty. Ever after, the horse would go almost frantic when there were any Keas about.”

Shepherds report that rabbits are sometimes killed by them, while dogs are often worried by their attentions. The birds are sometimes found eating the carcases of deer.

One case is known where a human body was torn about by them. On the Minarets Station a musterer was sent out to attend to some sheep on high country. The station is famous for its rugged and dangerous peaks, and is said to contain some of the wildest country on a sheep run. At night the man failed to report himself, and a search party was sent out to seek him. They found his body lying in a gully, where he had evidently fallen from the heights above. It was attended by two or three Keas, who had torn holes in his clothes, and already torn the flesh about. This is, I think, the only instance known where the Keas have attacked a human body. From the position of the body it is almost certain that the man was dead a long time before the birds began to maul him.