Māpunga, black shag, John Gould, Birds of Australia, 1840-48.
“Vilified, condemned, outlawed, and with a price on its head, the shag stands as the declared enemy of mankind. Its chief crime is that it has transgressed the law that any animal that comes into competition for food with man has no right to live, a crime that is held to deserve nothing less than indiscriminate persecution.” So wrote the ornithologist, WRB Oliver, in 1930 in a passionate protest against the bounty the New Zealand Acclimatisation Societies, the forerunners of the Fish & Game Councils, paid for each shag killed. Between 1890 and 1940 many colonies were exterminated because it was thought they were eating trout which, incidentally, were introduced into New Zealand. And even now, during the duck shooting season, they are still subject to persecution by hunters who do not realise they are now protected.
In evaluating the impact of cormorants on fish populations, it is important to distinguish between perception and reality. The perception of most people upon seeing a flock of shags feeding is that they are eating valuable sport fish that would otherwise be available to recreational anglers. The reality — confirmed by several scientific investigations — is that in most natural situations they have a relatively minor impact on commercial or sport fish populations. A 1996 study conducted by Margaret Fowle of the University of Vermont revealed that small yellow perch, rather than more prized catches, make up over 80% of the cormorant diet of about a pound of fish per day.
The black or great shag, is a cosmopolitan species and is distributed widely from eastern North America, Greenland, Iceland, across Europe and Asia, Africa and Australasia.
The great cormorant is the bird which since ancient times in China, were tamed and trained to catch and bring back fish to their owners, just as falcons were used to catch game in midair or on land. Sometimes they were completely domesticated, their eggs hatched under hens, and the young fed by hand on chopped eel and other fish. Training started when they were fully grown and feathered. One would be tied by a string to a stake at the water’s edge. At a whistle signal it was pushed into the water and tossed a bit of fish. Then, after a different whistle, it was pulled back and rewarded again. As soon as the bird got the idea, live fish were used. Then it was graduated to a boat or raft and a string tied around its neck so that it couldn’t swallow the fish it caught. With several of these trained birds, a Chinese fisherman was in business.
The Japanese also use the great cormorant for sport fishing and, in Elizabethan England, the Master of the Cormorants was a member of the royal household.
Of the world's 36 species of shag 12 are found in New Zealand and 8 of these are endemic. Members of the shag family belong to three groups based on the colour of their feet: black, yellow or pink. The term shag seems to have come about in reference to the crest on the head of some species.
Outside New Zealand, the black-footed shags are better known as cormorants. According to Schuckard, the names "cormorant" and "shag" were originally the common names of the two species of the family found in Great Britain, the Great Cormorant, Phalacrocorax carbo and the European Shag, P. aristotelis. "Shag" refers to the bird's crest, which the British forms of the Great Cormorant lack but the same species is called the Black Shag in New Zealand where it has a small crest on upper nape and neck. Despite this confusion, taxonomists still propose to divide the family into two genera with the name "Cormorant" and "Shag". The proposed division into subfamily Phalacrocoracinae "cormorants" and Leucocarboninae "shags" does indeed have some degree of merit although the entire family cannot be clearly divided at present beyond the super species or species-complex level. Several evolutionary groups are still recognizable, but a great deal of convergent evolution, such as cliff shags, is complicating matters. The resolution provided by the mtDNA is not sufficient to properly resolve several groups to satisfaction. In addition, many species remain unsampled for DNA, the fossil record has not been integrated in the data, and the effects of hybridization, known in some Pacific species, on the DNA sequence data, are unstudied.
According to Elsdon Best, Maori considered the shag to be the offspring of Terepunga. They were noted for their straight, unswerving flight and there are many sayings referring to this. They were not an important food supply but were occasionally eaten. Shaggeries in trees or on cliffs were visited to take the young before they could fly. These shaggeries were known by special names and were often given as evidence of occupation in the Land Court.
Cormorants from Henry E. Dresser's, A History of the Birds of Europe, ..., 1871-1896.
Black cormorant, great cormorant.
88cm., 2.2 kg., black with white patch on cheeks, facial skin yellow which in breeding season becomes orange red. breeding adult also has a white thigh patch, a small black crest on neck and filoplumes. The bill is grey, the eye green and the feet black.
Found throughout the main islands, including Chatham Islands, in coastal waters, estuaries, harbours, rivers, streams, dams and lakes up to the sub alpine zone.
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Gould, John, Birds of Australia, 1840-48.
Henry E. Dresser, A History of the Birds of Europe, including all the species inhabiting the Palaearctic region, 1871-1896.
Heather, B., & Robertson, H., Field Guide to the Birds of New Zealand, 2000.
Rob Shuckard, OSNZ.
Tuesday, 24 October, 2023; ver2023v1