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Stratigraphic records from lake sediment cores and slope deposits on Rapa Nui document prehistoric human impacts and natural environmental changes. A hiatus in sedimentation in Rano Raraku suggests that this lake basin dried out sometime after 4090–4410 cal yr BP and refilled only decades to centuries before AD 1180–1290. Widespread ecosystem changes caused by forest clearance by Polynesian farmers began shortly after the end of this drought. Terrestrial sections show a chronology of burning and soil erosion similar to the lake cores. Although changing sediment types and shifts in the pollen rain suggest that droughts occurred earlier in the Holocene, as yet there is no evidence for droughts occurring after AD 1180–1290. The timing of the agricultural colonization of Rapa Nui now seems well established at ca. AD 1200 and it was accompanied by rapid deforestation that was probably exacerbated by the island's small size, its droughty climate, and the rarity of primeval fires. Detailed records of a large interval of Rapa Nui's ecological history remain elusive due to the drought hiatus in the Rano Raraku sediment record. We find no evidence for a "rat outbreak impact" on Rapa Nui's vegetation preceding anthropogenic forest clearance.

Previous research has demonstrated a west-to-east decrease in zooplankton δ13C along the Alaskan coast. We extended the transect into the Canadian Arctic archipelago through the Northwest Passage in order to investigate whether this longitudinal gradient persists eastward. Contrary to the previous observations, zooplankton δ13C was found to be essentially invariate, despite a sampling survey length double that of the earlier studies. This resulted from zooplankton at the coldest and ice-bound stations being found to be enriched in 13C relative to what would be expected from the ambient water temperatures and calculated [CO2aq]. We suggest that this was due to the assimilation of ice POM which, as has been demonstrated for other forms of benthic algae, is enriched in 13C due to restraints on boundary layer diffusion. The present results therefore support other traditional, non-isotope research in suggesting that ice-bound polar foodwebs may be examples of aquatic systems where there is a functional energy connectivity between the attached and openwater environments.

The most intriguing mysteries of human history are those posed by vanished civilizations. Anyone who has seen the abandoned structures of the Maya, Machu Pichu, or Angkor is moved to ask the questions: “Why did the societies that constructed these structures disappear? What lessons can we learn from their experiences, and, who can say that we on the planet Earth will not succumb to the same fate?”

In the fall of 1954 as a graduate student at the University of Oslo, Norway. I wanted to escape the cold, dark rain season in Norway so I asked to be sent to the Canary Islands to collect algae specimens while skin-diving into under-sea caves along the coast. I flew from Oslo to the City of Las Palmas on the island of Grand Canary. Outside the city I set up camp on the beach at a beautiful site. On the second day while I was in the sea diving, children stole my tent, money, stove and equipment. Fortunately, the clothes, sneakers and my skin diving equipment, items I was wearing, remained. Before I left Oslo, my professor, Dr. Braarud told me that Thor Heyerdahl was staying at the Hotel Santa Catalina in Las Palmas with his wife Yvonne and new baby girl Annette.

Among the most enduring enigmas of Easter Island surrounds the giant Moai statues found there. Much has been written about these unusual behemoths, yet why they were made and how they were carried—some distances of over ten miles—is still shrouded in mystery. Fragments of nearly nine hundred such statues were cataloged earlier this century by Father Sebastian Englert (Figure 1), who lived most of his life and wrote extensively on Easter Island ethnology and archaeology (Englert, 1948). Many of these statues were still standing when Europeans first arrived there in the early-18th century, but nearly all were later thrown down and broken during the civil war and cast struggle that broke out around 1840 (Routledge, 1919). Clearly, superior engineering skills and stout materials were required in order to build and move these immense stones, many of which surpass 50 tons in weight and reaching heights of 10 meters. The presence of so many stone monoliths on one small island is indication of a robust and vigorous society. Yet, by the time the earliest European visitors arrived, Rapa Nui civilization was apparently already in significant decline, as no evidence of the engineering skills or materials necessary to move these statues were observed by European visitors. Roggeveen, the captain of the first European ship to visit Easter Island, wrote in his account of these statues: “At first these stone figures caused us to be filled with wonder, for we could not understand how it was possible that people who are destitute of heavy rope or thick timber, and also of stout cordage, out of which to construct gear, had been able to erect them; nevertheless some of these stature were a good 30 feet in height and broad in proportion.” (Roggenveen, 1722).

The destruction of fisheries world-wide can be traced to distinction of coastal habitats, polluting of spawning grounds and nursery areas and loss of near-shore wetlands, unrestricted coastal development and inadequate law enforcement. But the major cause by far is over exploitation of natural fisheries stocks. With modern technology and sophisticated gear there are currently 1.2 million large vessels hunting fewer and fewer fish. Since 1990 China has led the world in fishing production. In 1995, their fishing output was 25.2 million metric tons or, one fourth of the total world production. Throughout China the booming aquaculture industry is producing 53% of this aquatic production, employing fishery enhancement to closed cycle cultivation techniques.1 Returning from a recent invitation to visit aquaculture facilities and fish farms in northern and central China, it is clearly obvious as to why they are leading in this fast developing industry. This paper will discuss the problems of aquaculturing our foodstuffs from the sea (see Figures 1 through 12 on the Chinese aquaculture effort).