DEATH SENTENCES

Forest and Bird, Issue 59, 1 February 1941, Page 10

DEATH SENTENCES

By Blind Judges and Deaf Juries (By Waiatua.)

BIOLOGISTS and ecologists are revolting, in ever-increasing degree, against the passing of death sentence on any animal species the case against which is incomplete. A complete case against the New Zealand shag would require, among other things, proof by anglers that the shag destroys more trout, by eating them, than the trout he saves by eating eels. The anglers have no such proof. A complete case against the New Zealand hawk would require, among other things, proof by gunners that the hawk destroys more game birds by eating them than the game birds he saves by eating their enemies. The gunners have no such proof.

HARES AS FORESTERS.

If it were possible to appeal from the anglers and the gunners to a court of science for review .of the convictions and death sentences passed on the shag and the hawk, the court of science would find the case not proven; and it might possibly recommend the anglers and the gunners to read the following statement by Edward H. Graham, biologist of the United States Soil Conservation Service, on the place that the much-abused hare occupies in forestry operations in parts of the United States:— “The snowshoe hare of our Lake States is often blindly charged with intolerable injury to young trees. This is especially true on clean-cut or burnt-over areas where natural reproduction (of trees) results in very thick stands. Now the hare is a highly cyclic species, with ‘highs’ of large populations occurring at ten-year intervals. When the hare population is at its peak, the animals eat, girdle, or prune the young trees until the stand is so open that the hares may be easily seen by predatory mammals, owls and hawks. The hares must then retreat to thicker stands for protection. They may return at intervals of a few years whenever the trees have again thickened enough to form protective cover, and may thin out the stand recurrently until the bark becomes too thick to be palatable. Instead of being an unmitigated evil, however, the opening of the stand in each case permits the remaining trees to recover from their stunted

condition, helps to reduce the fire hazard, and minimises insect damage. In northern Minnesota the value of the thinning operations of the snowshoe hare is set at a high figure.” It should be added here that the snowshoe hare is indigenous to North America; and Mr. Graham’s finding concerning this particular hare would not necessarily apply to any hare or other creature that had been imported. Between the native and the imported, biologists generally find it necessary to draw a definite line.

NO INDEPENDENT BIOLOGIST.

Many generations of foresters in America have failed to value at a high figure the thinning operations of the snowshoe hare, and many generations of anglers and gunners have failed to value at a high figure the thinning operations of shags and hawks, which always take the weakest victims first, and which prey not only on game but on game-enemies. The reproof handed out to American foresters by an American biologist like Edward H. Graham might also be handed out to anglers and gunners by a biologist of similar capacity and independence—if New Zealand possessed one. The lack of an independent ecological biologist is very serious in this country. Scientific societies composed of Civil Servants who are forced to consider departmental interests are a poor substitute. The Court of Science to which reference is made above (imaginatively, of course) would be a misnomer if the word “Science” were interpreted on narrow conventional lines, as is usual. Graham, in the article quoted above, deals mainly with ecology, and he writes: “In a broad sense, ecology is much more a process of thought than a science. To think ecologically requires only a knowledge of facts and an ability to relate them correctly.” Ecology despises blind adhesion to conventional rules. Example: The gardener, in his weeding operations, removes the weeds from a shade-loving species, which therefore nearly dies. The gardener, after one or two experiences of this sort, leaves a little oasis of weeds in the long sweep of his border, and beneath

the weeds the delicate species is surviving a long dry summer. In other words, the gardener has correctly related observed facts. But the owner, seeing the weeds and not the thing they shelter, considers the gardener is shirking and sacks him. The owner has incorrectly related the observed facts, missing out the most important. The owner’s thinking is of the angler-gunner type. The gardener, probably without knowing it, is an ecologist.

“MERELY WEEDS.”

Ecology has been defined as the science of the relation of living things to their environment. The man to whom all weeds are just weeds, to whom all shags are just trout-killers, and all hawks are just quail-killers, is the reverse of an ecologist. In predatory nature there are few all-inno-cent species, few all-guilty species. Guilt or innocence is a question of balance. Balancing the virtues and the vices of a species is very complex, and only simple minds can unravel the complex in simple ways. To draw conclusions from single acts of predation is an over-simplification that always ends in error. It is on record that one simple soul introduced a lantana species to Hawaii. He never thought that this plant would become aggressive, but it did. Another simple soul introduced to Hawaii the cooing turtle dove from China and the Indian mynah; he never thought that they would become agents disseminating lantana, but they did. But the mynah had a virtue protected the Hawaiian grasslands and young sugar-cane from army worms. A third soul, perhaps not as simple as the two others, imported foreign insects to eat lantana seed and to check lantana’s spread. The insects succeeded in this, and also in reducing the seed food of the mynahs, which began to decrease. Then back came the army worms. To deal with problems of this kind requires more ecology than to write an annual report for an acclimatisation society.

“PURE STANDS” AND BIRD LIFE.

How many generations of forestry were required in order to discover that pure pine stands are an afforestation error? According to Graham, “soils are depleted under a uniform type of forest cover, and disease is prevalent because it can spread more easily than in mixed stands.”

Nature herself does not grow trees in pure stands, and New Zealand birds have not been brought up to trees growing in pure stands, much less to exotic trees in pure stands. Graham records that in European pure stands of spruce or pine “insect damage is so widespread that bird boxes are being installed in an attempt to restore artificially some semblance of the biological balance which was lost by man’s failure to think ecologically.” That is to say, the creators of an unnatural forest a forestic monotone —ignore the birds’ part in forestry, and now seek to remedy their ignorance. Bird-loving men who have queried the wisdom of one-type birdless forests have been derided as hobbyists. They were, in fact, ecologists, whom time has avenged.

Nature consists of “many facets related not as single species, but as a mosaic, the pattern of which is not appreciated at first glance, but must be seen in different lights to disclose its true design and its real worth.’’ Public policy in New Zealand is made either by first-glancers or by people who, on second glance, find the pattern too complex, so they shut their eyes, make a blind plunge with a pin, and found public policy on that facet on which the pin happens to strike, ignoring the rest of the mosaic. By this kind of blind man’s buff a nation can gamble away its soil, and also its soul. Some nations have done so. America and New Zealand are well on the road, but America at least has the merit of an earnest seeking after ecological truth and a new attitude to Nature’s resources.