MY FAVOURITE PLACE ON EARTH
might be a sea turtle hatchery. Not only that the surroundings are mostly paradisic, more or less pristine beaches which form part of tropical coastal areas – but that the sand underneath me contains hundreds or thousands of potential sea turtle hatchlings. The sand surface could start to move any time to reveal a tiny nose which made its way up to the fresh air, resting and waiting for its companions to do so as well. There is so much life in this small area, and a great part of this life depends on our work, our decisions, and our commitment.
Someone once said to me that people like to work in sea turtle hatcheries because they can “play god”. And even though I first didn’t fully agree with this (because “playing god” always sounds like something bad and unethical), I have to admit that he might be right to some point.
I love the hatchery work because I feel responsible for these lives, I feel challenged and also “needed” in this world. It is something valuable and satisfying to observe a hatching event; hatchery work allows to take part in the creation of new life and to see some first, direct results from the conservation work.
And there is nothing bad about playing god when many other humans before me have played god as well, which is part of the reason why we have to take care of these creatures now.
HATCHERY WORK IS CHALLENGING
because you need to assure that the hatching success is always as high or higher than under natural circumstances – otherwise the hatchery would lose its justification. The hatching rates do still depend on the environment and its natural forces, but they also depend to a great degree on us humans, our care and our applied methods.
Apart from a high success rate, there are other things to consider: the hatchlings must be strong and fit and the sex ratio must be balanced or better: ressemble the natural, historical one.
The sex ratio is known to depend on nest temperature. But most of the time, the sex ratio which should be aimed for, and the one that is actually given upon hatching, are totally unknown. Sex determination on hatchlings is difficult and mostly not justifiable (as you need to actually kill the hatchlings for the examination), and for many sea turtle populations, the actual, natural sex ratios are not revealed yet. Therefore, not every conservation project in this world knows what nest temperature should be maintained in order to achieve a good, self-sustaining sex ratio under the local circumstances.
Hatchery work contains a high level of insecurity at all times, and a great potential for human failure.
SPEAKING OF HUMAN FAILURE,
I would like to give the example of the (now virtually extinct) Leatherback Turtles in Rantau Abang, Malaysia (see this article as reference).
The once world-famous Leatherback population of mainland Malaysia was suffering high mortality rates, mainly due to fishing by-catch, alongside low natality rates due to egg collection. Therefore, a hatchery program was started as early as the 1960’s.
As egg collection on the beach continued though, only between 10 and 35 % of all nests laid got transferred to the hatchery during the first decades. As a consequence of this and of inappropriate incubation methods, hatching rates were between 40 and 60 % only.
But not only the hatching rates were low; the sex-ratio turned out to be highly female-biased as temperatures were too hot. This was only fully revealed decades later when the returning, then mature females laid a high percentage of unfertilized eggs. This again led to low hatching rates of around 35 % in the 1990’s.
All in all, too few hatchlings got released to sustain the population which continuously suffered high mortality rates. The number of hatchlings released per year varied between 5.000 and 45.000 during the 1970’s and 80’s. Even though egg collection was banned in the late 80’s and all nests laid got transferred to the hatchery, the number of hatchlings released per year decreased to less than 5.000 in the 1990’s.
All this happened decades ago when research about incubation methods and temperature-dependency was not yet at the level of today. The poor hatchery work was not the reason for the population decline; it just did not succeed to impede it. In the end, this example shows that hatchery work is a sensitive matter after all.
Hatchery work holds a great potential for mistakes. Eggs need to be transferred as soon as possible after oviposition, they must not be moved around too much, the nest depth, dimension and location must be right to secure favourable conditions (nest temperatures, oxygen flow, sand moisture etc..) Nests must be protected from natural predators, bacteria and fungus, and once the turtles have emerged from the sand they need to be released as soon as possible at an appropriate time and location.
After all, the relocation of nests poses a further interference with nature. Such interferences are said to always result in some predictable and some unpredictable, not-visible-at-first-sight, negative outcomes. Therefore,
CONSERVATIONISTS SEE THE USE OF HATCHERIES
as the last option in the protection of sea turtles. This means that hatcheries should only be used when they are strictly needed because nests cannot be left on the beach. This is mostly the case where egg collection by humans occurs, or where exorbitant mortality rates threaten the survival of a greatly diminished population. Hatcheries are mostly used for severely declined populations, when conservationists cannot even risk the loss of one single sea turtle hatchling.
Hatcheries – in some parts of the world – are one last, desperate step of action by conservationists to prevent sea turtles from going totally extinct. And another factor contributes to the great level of insecurity that comes along with this type of work:
Due to the late sexual maturity of some sea turtle species and populations (the Green and Hawksbill Turtles in the Pacific Ocean for example are said to reach maturity between 30 and 40 years of age), the effects of many younger hatchery programs are not visible yet. This is because population sizes are mostly estimated by the development of the nesting population on a certain beach. For many years and decades, it remains questionable if the egg protection efforts are effective and succeed in stabilizing the sea turtle population. In these cases, it needs some very dedicated conservationists who are willing to commit a lifetime for a potentially hopeless cause.
IF APPROPRIATE TECHNIQUES ARE APPLIED,
hatcheries can be a perfect tool to increase sea turtle population levels. Hatchery work enables to increase natality rates to the level where they outweigh the mortality rates. As most of the mortality happens in the ocean, it is not directly influencable by us people on land and needs some long-term measures, behaviour changes and policy changes. Therefore, increasing the natality rates is a more effective protection tool in the short run, as it has immediate outcomes.
The hatchery work includes the transfer of nests to the hatchery, their monitoring, hatching and release events, the excavation of older nests and finally the analysis of the obtained data. These last two steps make it possible to reveal potential mistakes in the hatchery management, as they reveal hatching and emergence success rates, factors that influence these rates and how they might be interconnected, and the potential death causes of sea turtle embryos.
By knowing all this, it is possible to improve the hatchery work and to raise the success rates. If temperature patterns are fully understood, it is even possible to “work against” negative natural influences like extreme weather periods. Yes, hatchery work gives a great potential to work against nature. For egg protection,
HUMANS MUST INTERFERE WITH NATURE
as the nests must be protected from natural threats like predators and inundation. These threats have always been there and are not the reason for the population decline – only now there is an imbalance as the natural threats have stayed constant while the population numbers have not. Another concern are raised sand temperatures on nesting beaches due to climate change and the removal of beachfront vegetation, which affect sex ratios and increase embryo mortality. In this case, interference with nature becomes even more important. The artificial shading of nests in hatcheries helps to work against the human-induced heating, until evolution might be able to adapt to these new circumstances. Only when we achieve to stabilize sea turtle populations by reducing human-induced mortality and raising natality, we can leave sea turtle nests unprotected and unobserved on the beach – just as it is supposed to be.
So to conclude this thought: Interference with nature – in my opinion – is highly justifiable if the reason for this interference is prior interference by other humans. Just as the thing with playing god.