Green, William Spotswood (1847–1919), marine scientist, was born 10 September 1847 in Youghal, Co. Cork, the only son and eldest of six children of Charles Green, JP, merchant of Youghal, and his wife Catherine Frances, daughter of Walter Fitzsimons. Educated at Rathmines School, Dublin (1859–61), Midleton College (1861–7), and TCD (1867–71), he spent his childhood in the family home on the seafront in Youghal, where an obsession with boats, the sea, and fishing began. His first written observations on natural history date from this period and include records of distribution of molluscs in Youghal Bay. Diaries beginning in 1865 record observations on his aquaria and contain watercolour illustrations. During undergraduate years his diaries record shore-collecting in Dublin Bay and (1869) a week's cruise in a trawler. The courses he took included experimental physics, logic, mathematics, and physics. While his over-riding interest was in marine science, he took holy orders after graduating in 1871. He was ordained deacon in the Church of Ireland (1872) and priest (1873), and was appointed curate of Kenmare in 1874, moving in 1877 to Carigaline, where he became rector in 1880.
In the course of his ministry Green undertook geographical exploration in the Orinoco delta, the Swiss Alps, Mount Cook in New Zealand (1882), and the Canadian Rocky Mountains – studying glaciation in the latter three. The Mount Cook expedition was supported by the RIA and a scientific account was published in its Transactions, followed by a popular book and a paper presented (1884) to the Royal Geographical Society, which elected him to fellowship in 1886.
In 1885 and 1886 Green organised the logistics of the RIA's first studies of the offshore marine fauna of Ireland. In 1887 he was appointed by the RDS to make a study tour of three south-coast fishing ports, and was elected to honorary membership. The following year he undertook his last foreign exploration, to the Selkirk glaciers in Canada, and on the same trip made a study of fishing and fisheries research on the North American Atlantic coast. His final purely zoological marine study took place in 1889, funded by the British Museum.
He retired from pastoral duties in 1890 on appointment as one of the three inspectors of Irish fisheries, and moved to 5 Cowper Villas, Dublin. The same year he directed a major exploratory fishing cruise on the south and west coasts of Ireland. In 1891 the RDS commissioned a four-month cruise in which Green not only took entire responsibility for gear, personnel, and choice of the vessel but skippered it throughout. Appointed to membership of the newly established Congested Districts Board in 1891, he was thereby able to apply many of his ideas on the infrastructure for fisheries. Elected MRIA in 1895, he led one more expedition on behalf of the Academy, the first scientific exploration of Rockall, in 1896.
He was appointed chief inspector of fisheries when a permanent government fisheries authority was established in 1900, a position that he held until retirement in 1914, after two years' extension beyond normal age. He was created CB in 1907. Besides his normal duties as director and the writing of unusually comprehensive annual reports, his work included playing a major part in the design of the research vessel Helga II and of the Ovoca, Ireland's first motor fishing vessel, in which he paid particular attention to the comfort and well-being of the crews. A highly competent marine historian, he published two particularly important papers: on the sea fisheries of Ireland (1902) and on the wrecks of a number of the ships of the Spanish armada (1906).
In spite of bronchial problems, Green led a vigorous life as seaman and mountaineer, was noted for his sense of humour, and excelled in personal relations with fishermen, which was of the greatest value in gathering information on the grass-roots state of the industry. He was also an accomplished writer and watercolourist. He died 22 April 1919 and was buried in the churchyard of Sneem, Co. Kerry. Some of his papers are deposited in the Turnbull Museum, Wellington, New Zealand.
He married (1875) Belinda Beatty Butler; they had one son and five daughters. The son, Charles (b. 1876), accompanied his father on later expeditions and later served as chief inspector of fisheries. W. S. Green exerted a profound influence on the development of fisheries in Ireland. While the initiatives were taken first by the learned societies and next by the government, their great success may truly be attributed to his mind and character.