Trees, shrubs, and herbs were sampled inside and outside an exclosure in a 230-year-old Pinus resinosa forest in north-central Minnesota from 1946 to 1969. Prior to the building of the exclosure in 1937, white-tailed deer had existed at or above starvation population densities for 10 or more years. Overbrowsing continued outside the exclosure until 1945 when the deer were virtually eliminated by hunting. Since then deer numbers have gradually increased. Before 1937, severe browsing had apparently removed all tree reproduction greater than 1-2 years old. Since 1937, inside the exclosure the occurrence of seedlings and saplings has increased greatly and has followed a normal successional sequence dominated by finus strobus with lesser amounts of Betula papyrifera, Acer rubrurn, Quercus borealis, and Abu•s balsarnea. Outside, tree reproduction was scarce until after 1945; then Pinus resinosa, P. strobus, and Betula papyrifera saplings increased substantially. Only P. resinosa and B. papyri/era have grown above the sapling class in appreciable numbers, probably because B. Pa_Pyrifera is of low preference as deer browse compared with the other intermediate species, Pmus strobus, Acer rubrum, and Quercus borealis. Thus, moderate-to-high browsing has continued to inhibit successional development.

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The free-ranging colony of gibbons established on an island in the Gulf of Thailand by the SEATO Medical Research Laboratory in 1966-1967 was terminated in 1970. Out of the 20 gibbons originally introduced, four adults of each sex remained until near the end of the project. The four females each gave birth to one infant. In all cases the young were conceived five or more months after pairbonds and ranges had stabilized into a more natural-like pattern, with fairly regular morning inter-group vocal sessions and territorial boundaries between groups containing the most feral individuals.The maximum effective breeding density on the 60-acre island was found to be about four or five pairs. The chances of reproductive success appear to be maximized in a free-ranging colony containing several pairs by maintaining a one-to-one sex ratio and allowing enough space so that natural patterns of social behavior may be expressed. The amount of area required per group may vary with the individual gibbons and the environment, but we found it to be about ten acres.The SEATO Medical Research Laboratory in Bangkok, in collaboration with the Delta Regional Primate Research Center, Covington, Louisiana, established a colony of free-ranging gibbons (HyZobates Zar) on

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