SOCIAL AND ECONOMIC VALUES OF MARINE BIRDS 



177 



Guano 



Peruvian guano beds are currently being 

 managed on a sustained-yield basis; the har- 

 vest, as in the days of the Incas, depends en- 

 tirely on the amount of guano deposited each 

 year. Conservation and management policies 

 have resulted in a steady increase in the 

 amount extracted, from around 20,000 tons in 

 1900 to over 200,000 tons in 1971 (Lockley 

 1973). 



The islands off south and southwest Africa 

 are also commercial producers of guano. The 

 annual yield from these breeding colonies 

 averaged 3,971 tons in the 12-year period, 

 1961-72. In 1969, guano brought 4.75 Rands 

 (equivalent to $7.11) per 200-pound bag. 

 South African gannets are apparently de- 

 positing guano that is worth twice as much as 

 the fish they consume to produce it (Jarvis 

 1971). 



Indirect Commercial Benefits 



Marine birds also play significant roles in 

 the economies of the world's oceans, where 

 algae, invertebrates, fish, seabirds, mammals, 

 and man interact in complex ways. The bio- 

 energetics and nutrient cycling in ocean eco- 

 systems is even less well understood than the 

 contributions seabirds make to man's dollar 

 economies. 



Sanger (1972) has conservatively estimated 

 that in the subarctic Pacific region alone, 

 birds consume from 0.6 to 1.2 million tons of 

 food and return from 0.12 million to 0.24 mil- 

 lion tons of feces each year. 



Marine bird excrement is especially rich in 

 nitrates and phosphates, which phytoplank- 

 ton, the basis of ocean food pyramids, re- 

 quires. Marine birds then, at least to some ex- 

 tent, help to sustain the northern commercial, 

 recreational, and subsistence fishing indus- 

 tries. The fisheries in turn sustain seals and 

 certain other mammals which are also essen- 

 tial elements of northern subsistence and rec- 

 reational economies. Thus, marine birds con- 

 tribute economic benefits indirectly as well as 

 directly by serving as critical links in ecosys- 

 tem food chains (Tuck 1960). 



Subsistence Uses 



The use of marine birds and their products 

 does not have to be commercial to be eco- 

 nomic. Economics is the science of the alloca- 

 tion of scarce resources. Any resource, regard- 

 less of whether it is bought or sold, has value 

 to people and is therefore an economic com- 

 modity. Thus, any society has an economy 

 whether or not it uses cash, and when the 

 meat, feathers, or oil of marine birds are used, 

 the birds have economic value. The problem, 

 of course, is that of trying to determine just 

 what this value is when a cash medium does 

 not exist. 



One of the ways to estimate this value is to 

 assign implicit gross dollar values to seabirds, 

 based on what it would cost to replace prod- 

 ucts derived from them with store-bought 

 items of a similar, or substitutable, nature 

 (this is a gross rather than a net value because 

 it does not include the cost of guns, ammuni- 

 tion, transportation, etc., required to harvest 

 and process the resource). 



There have been many occasions in the past 

 when it would have been physically impos- 

 sible to find substitutes for seabird products. 

 In such cases, and where seabirds may well 

 have meant the difference between life and 

 death, the economic value of the resource 

 could be considered a plus infinity. 



There are probably few, if any, places in the 

 world today where people would starve if they 

 could not obtain marine birds. However, there 

 are still many situations where available sub- 

 stitutes are poor, or very expensive. And 

 there are others where, even though the birds 

 are no longer necessary for economic survival, 

 they are still very important in terms of socio- 

 cultural traditions. According to Tuck (1960), 

 "Wherever a wild animal is important to the 

 economy of a people, its capture and use be- 

 come part of the tradition of that people." 

 Thus, while economic values can be measured 

 in terms of substitutable store-bought foods, 

 social and cultural values cannot be. To force 

 complete dependence on a people by flying in 

 foods from "Outside" is often socially intoler- 

 able because it tends to remove pride, a sense 

 of worth, and therefore the reasons for living. 



Marine birds have served as important 

 sources of food in the Faeroes Islands for cen- 



