<P> By that time, 21 species of trees and all species of land birds became extinct through some combination of overharvesting / overhunting, rat predation, and climate change . The island was largely deforested, and it did not have any trees more than 3 metres (10 feet) tall . Loss of large trees meant that residents were no longer able to build seaworthy vessels, significantly diminishing their fishing abilities . One theory regarding the deforestation that caused such ecological and social damage was that the trees were used as rollers to move the statues to their place of erection from the quarry at Rano Raraku . Deforestation also affected agricultural production on Rapa Nui . At first, the native tropical forests provided ideal shade cover for soil . But with many of the native forest being destroyed, the topsoil became eroded causing a sharp decline in agricultural production . This was further exacerbated by the loss of land birds and the collapse in seabird populations as a potential source of food . By the 18th century, residents of the island were largely sustained by farming, with domestic chickens as the primary source of protein . </P> <P> As the island became overpopulated and resources diminished, warriors known as matatoa gained more power and the Ancestor Cult ended, making way for the Bird Man Cult . Beverly Haun wrote, "The concept of mana (power) invested in hereditary leaders was recast into the person of the birdman, apparently beginning circa 1540, and coinciding with the final vestiges of the moai period ." This cult maintained that, although the ancestors still provided for their descendants, the medium through which the living could contact the dead was no longer statues, but human beings chosen through a competition . The god responsible for creating humans, Makemake, played an important role in this process . Katherine Routledge, who systematically collected the island's traditions in her 1919 expedition, showed that the competitions for Bird Man (Rapanui: tangata manu) started around 1760, after the arrival of the first Europeans, and ended in 1878, with the construction of the first church by Roman Catholic missionaries who formally arrived in 1864 . Petroglyphs representing Bird Men on Easter Island are exactly the same as some in Hawaii, indicating that this concept was probably brought by the original settlers; only the competition itself was unique to Easter Island . </P> <P> According to Diamond and Heyerdahl's version of the island's history, the huri mo'ai--"statue - toppling"--continued into the 1830s as a part of fierce internal wars . By 1838 the only standing moai were on the slopes of Rano Raraku, in Hoa Hakananai'a in Orongo, and Ariki Paro in Ahu Te Pito Kura . A study headed by Douglas Owsley published in 1994 asserted that there is little archaeological evidence of pre-European societal collapse . Bone pathology and osteometric data from islanders of that period clearly suggest few fatalities can be attributed directly to violence . </P> <P> The first - recorded European contact with the island was on 5 April (Easter Sunday), 1722, by Dutch navigator Jacob Roggeveen . His visit resulted in the death of about a dozen islanders, including the tumu ivi' atua, and the wounding of many others . </P>

Where are the moai statues located on easter island