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In the story that I was told, the older traditional hunters of Torres Strait believe that loggerhead turtles laid their eggs under water on the reef. As a result of their long hunting tradition, they recognize and have specific names for green turtles, hawksbill turtles, flatback turtles and loggerhead turtles. Each species is known to be part of the marine community of Torres Strait; however, only three species (green turtles, hawksbill turtles, flatback turtles) are known to nest on the islands. Because the hunters also collect turtle eggs, they know that each of the three species does not nest on every island. Green turtle nesting is the most widespread and occurs on most of the islands in the area. Hawksbill turtles nest on many of the islands and flatback turtles nest on only a few. In contrast, loggerhead turtles are not known to nest on any islands in Torres Strait.

When asked the question “Where do loggerhead turtles lay their eggs?”, traditional hunters have told me that loggerhead turtles lay their eggs “…out on the reef flat under coral”. At first, this answer sounds absurd because anyone who has read the scientific literature on marine turtle ecology or who has spent time working at a marine turtle nesting site knows that marine turtle eggs will not develop in water; in fact, developing embryos drown, if the nest is inundated for very long. However, the answer is not absurd at all; it is founded on good observations.

The apparent contradiction between the traditional knowledge and scientific information suggests that one of the two is in error. Part of the contradiction emanates from the incongruity between the requirement that to be good, traditional hunters and scientists must be good observers. Torres Strait Islanders (TSI) have amassed a considerable knowledge about the marine turtles that they hunt. This information is shared among hunters and taught to the young hunters; it is incorporated into cultural life of the people. Among other things, they know that four recognizable species live in the area. They know that marine turtles lay eggs on the beaches and the size of the eggs produced by each species. They know where and when to look for nesting turtles and they know how to find the buried eggs. If a hunter says that loggerhead turtles do not nest on the islands, he is stating fact based on his observations and those made by other hunters.

TSI hunters know that three species lay their eggs on land and that loggerhead turtles are not seen nesting on the beaches. They recognize the eggs of marine turtles because they dig up clutches laid on the beaches; they know they find marine turtle eggs and egg shells among the coral out on the reef-flats during the turtle nesting season while they are hunting other food species. Because they find turtle eggs among the coral and because loggerhead turtles are not found nesting on the beaches, they have interpreted their observations to mean that loggerhead turtles are the ones that lay the eggs among the coral. The observations are correct but the interpretation drawn from the information is not.

Resolving the contradiction requires a knowledge of the reproductive biology of the turtles and careful listening. First of all, loggerhead turtles do not nest on the islands of Torres Strait. In Queensland, they nest on islands and along the mainland coast at the southern end of the Great Barrier Reef, mostly south of the Tropic of Capricorn.

Second, when a marine turtle finishes nesting, one or more eggs may remain in the cloaca or in the distal portion of the oviduct. As the turtle returns to the water, the cloacal muscles relax and any remaining eggs are released. Sometimes this happens while the turtle is still on the beach, but it also happens after the female has begun to swim away from the island. In this case, the eggs settle to the bottom where they come to rest among the coral and rock of the reef. Scavengers may consume the contents of some or all of the eggs, but the empty shells remain. In places where several turtles may be nesting during a nesting season, the number of released eggs can build up to be obvious in a short period of time. Under water, the depredated egg shells look like the empty shells found in nests on shore after the hatchlings have emerged. When the TSI hunters said they saw marine turtle eggs underwater out on the coral reef, they were correct.
Third, that loggerhead turtles lay eggs underwater was stated in the same manner as other observations, i.e. as if it were fact. However, when asked if any of the hunters had ever seen loggerhead turtles actually laying eggs underwater the answer was ‘No’. The information was deduced from observations.

The human desire to have an explanation that makes sense out of observations transcends cultural differences. The conclusion drawn by the TSI hunters is consistent with their observations and provides an explanation of the anomaly in the number of types of turtles living in the area and the number of those types nesting. The contradiction occurs when the listener hears the observations but discounts the bulk of the information because some of the information (in this case the interpretation) contradicts the expected and/or their personal experience. If the listener had experience in the water over the reefs of Torres Strait during the turtle nesting season, he too would know that eggs can be found regularly out on the reef flat.

The observation is not in contradiction of the biology of marine turtles – marine turtles do not nest under water; but they can and do deposit eggs under water. This is more than a subtlety of language; it has to do with listening carefully. Scientists have too often not listened carefully when information has been shared; as a result traditional phenological information and direct observations have been discounted because they were bundled with erroneous conclusions during the telling.

The phenological knowledge of biological phenomena that supports individual and cultural activities is based on good observations and correlates with definable, regular events over a long temporal scale. Phenology is part of good science because it relies on good observation and synthesis of information. For people without convenient communication or for whom transportation over distances is limited, phenological conclusions are likely to be based on incomplete observations. For example, at one time the earth was thought to be the center of the universe; it was also thought to be flat. Both of these are erroneous interpretations based on data stemming from incomplete observations.

The accuracy of observations made by hunters and traditional people have been overlooked because the interpretations do not fit with information collected over different spatial and/or temporal scales and in a different cultural context. It must be remembered that all knowledge occurs within a cultural context. Because they were separated by linguistic and cultural boundaries, the TSI people were not able to compare their observations on loggerhead turtle nesting with those made by Aboriginal people living more than 1000 km to the south where loggerhead turtles nest. If the information had been available, the people of Torres Strait would have known that loggerhead turtles nested on land just like green, hawksbill and flatback turtles. They simply did not have all the necessary information on which to explain their observations. Their mistake was in stating observations and interpretations as fact. The mistake of the scientist was in not listening to what was said.

Bradley asked the question, “How can a whitefella know it all?”. The short answer is that he cannot but neither can anyone else. Both traditional knowledge and scientific information are required to facilitate the long term survival of marine turtles and human cultures in today’s complex world. We must improve communication. We can start by carefully listening to the Elders.

BRADLEY, J.E. 1998. How can a whitefella know it all? Indigenous Science – Western Science and Marine turtles. In: R. Kennett, A. Webb, G. Duff, M. Guinea & G. Hill (Eds.) Marine Turtle Conservation and Management in Northern Australia. Centre for Indigenous Natural and Cultural Resource Management and Centre for Tropical Wetlands Management, Northern Territory University, Darwin, Australia. pp. 25-32.

JOHANNES, R.E. & J.W. MACFARLANE. 1991. Sea turtles. In: Traditional Fishing in Torres Strait Islands. CSIRO, Australia. pp. 53-72.