abstract than the Shabman-Bertelson paper suggests. Houses located a block or 

 more from a wetlands can have a greatly enhanced real estate value from their 

 proximity to the wetland, if all of the lots in the area are large, even if the 

 lots are all a block or more from the wetland. The range of physical charac- 

 teristics over which realty development and wetlands preservations benefits are 

 substitutes for each other needs to be defined more carefully. 



38. Thomas, M., B. Liu, and A. Randall. 1979. Economic aspects of wildlife 

 habitat and wetlands. Midwest Research Institute and Water Resources 

 Council, Kansas City, MO. 88 pp. 



This is a comprehensive treatment of the conceptual and empirical problems 

 that arise in valuing wetlands habitat outputs. Perhaps the major contribution 

 of the monograph is that it forcefully demonstrates the path-breaking nature of 

 the work of Hammack and Brown (see [10]). It reviews the work of biologists in 

 quantifying the habitat versus recruitment class relation, and the complex 

 interaction between habitat values and socially desirable environmental 

 attributes. Thomas, Liu, and Randall point out that estimation of the marginal 

 value product of wildlife habitat is difficult due to the provision of joint 

 products. Thus wildlife observation and sport hunting are, to some extent, joint 

 products that are supplied by wildlife habitat. 



Other difficulties in estimating the marginal physical productivity 

 relation include multiple habitats (breeding, overwintering, and migratory 

 habitats), habitat heterogeneity, and habitat indivisibility. The last named 

 identification problem stems from the use of multiple habitats by certain 

 species; it is the difficulty in distinguishing the particular contribution of 

 one of several types of habitat that are needed by the species to complete the 

 life cycle. 



39. Beal , K.L. 1980. Territorial sea fishes management and estuarine 

 dependence. Pages 67-77 in V.S. Kennedy, ed. Estuarine perspectives: 

 proceedings of the fifth biennial international estuarine research 

 conference. Academic Press, New York. 



The article points out that estuarine zones and saltwater coastal marshes 

 and swamps are essential habitat for a number of economically important finfish 

 species. Beal believes that there is little data on the value and volume of the 

 commercial catch for shallow Atlantic saltwater fisheries (see, however, the 

 important paper by Peters, Ahrenholz, and Rice [30] for presentation and 

 interpretation of data on the volume and value of the wetland dependent finfish 

 and shellfish catches). Beal asserts that the value of the recreation catch of 

 ceYtain target species is greater than the value of the commercial catch. He 

 believes that regulation of marine fisheries to prevent heavy overfishing is 

 needed to preserve these precious resources. 



40. Owens, R.E., III. 1980. The economic value of Virginia's coastal wetlands 

 as an erosion control device. M.S. Thesis. Virginia Polytechnic Institute 

 and State University, Blacksburg. 130 pp. 



The author analyzes data that show that wetlands erode as rapidly as 

 fastlands on the Virginia shores of the Chesapeake Bay, but wetlands do impede 



34 



