Landsat has not found the applications in the monitoring of seasonal events 
that one might have expected. Solid work has been done by Ashley (1971) and 
others in the "Green Wave" and "Brown Wave" experiments in the United States, 
but the main interest in the monitoring of phenological events has remained in 
agriculture. This is somewhat of a disappointment, because Landsat is well adapted 
for the monitoring of seasonal changes. 
Wildlife 
Monitoring in wildlife studies is aimed at both habitat and the direct obser- 
vation of animals. Remote sensing contributes to habitat studies through its role in 
vegetation mapping, forest inventories and agricultural surveys, which all contain 
basic data on habitat. Wildlife scientists are also concerned with remote sensing 
programs on inland water bodies and oceans. For instance, upwellings in the 
oceans, which are to some extent detectable by remote sensing of surface 
temperature and colour, are associated with essential enrichment of the food 
sources for sea birds and marine life. Also, the ability to detect and observe oil 
spills is a prerequisite to the protection of sea birds, ducks and geese and of 
shoreline habitats. 
A recent contribution to habitat surveys has been the development of 
operational systems for the inventory of ponds and lakes with Landsat data. Ponds 
over approximately 1.6 hectares in size can be recognized with high accuracy using 
a single spectral band, and substantial progress has been made in estimating smaller 
water areas by combining information from several bands (Work and Gilmer, 1976). 
Remote sensing, in an international monitoring system combining ground 
observations, light aircraft and data from Landsat, is relied upon for an annual 
evaluation of duck populations, leading to the establishment of hunting regulations. 
Gilmer, Klett and Work (1975) describe the potentially significant contribution of 
Landsat. Satellite imagery is also used to monitor goose populations (Reeves, 
Munro and Marmelstein, 1975), and to observe the receding of the snow line, which 
in turn is used to predict the nesting success of lesser snow geese (Kerbes and 
Moore, 1975). 
Aerial photography too plays an important role in the direct observation of 
wildlife populations, often as a supplement to visual observations in the census of 
gregarious or migratory birds (Figure 5). Heyland has long been a proponent of the 
use of vertical aerial photography and light aircraft for the census of geese, other 
migratory birds, musk oxen and sea mammals. His scales of photography are often 
in the order of 1:3,000 and 1:5,000, but can be as large as 1:150. for. detailed 
examination of individual animals (Figure 6). He provides excellent examples of 
such photography in the proceedings of a 1975 workshop on remote sensing in 
wildlife held in Quebec City (Heyland, 1975). These proceedings also describe how 
Meyer's versatile resource inventory system, based on small format and conven- 
tional aerial photography, has found application in the monitoring of waterfowl 
populations and habitat (Meyer 1975). 
Coastal zones, shorelines and oceans 
In recent years the resources of coastal zones and continental shelves as well 
as the oceans themselves, have commanded increasing attention not only because 
of the direct value of the resources involved, but also because we have begun to 
understand the full effect of man's potentially destructive impact through 
pollution, depletion of fish stocks and land use changes that lead to degradation of