This creature appears like something out of this world, but actually it has been living on this planet longer than most animal we can find nowadays. The name is horseshoe crab despite they don’t really look like horseshoe nor a crab.
The origin of this animal can be tracked down to 450 million years ago. Yes, they belong to those ‘ancient’ animals, and have outlived the dinosaurs, that we can say that this animal is actually the real living fossil.
In fact, they have survived several ice ages, the Great Dying, the formation and breaking up of Pangaea continent, even the asteroid impact that killed dinosaurs. But nowadays, they are under the threat of extinction. What’s more destructive compared to all those things above that it can put the threat?
Well, about three decades ago the population of this animal was plenty, but a discovery about its blood made by researchers changed the condition. What’s with the creature’s blood? And what about its current condition nowadays? Here in this article we are going to talk about that.
The Blue Blood
Here, we are going to talk about blue blood. No, it is not about royal family or such kind of thing, but rather about the real blue blood. And yes, the color of this creature’s blood is blue because instead of carrying iron in its blood it carries copper.
Horseshoe crab’s blood is a little bit different from other living creature’s blood. First, it uses hemocyanin instead of hemoglobin to carry oxygen throughout its body. While hemoglobin contains iron to make a bond with the oxygen, hemocyanin uses copper as mentioned above to form the bond.
But apparently hemocyanin is not the only unique thing contained in horseshoe crab’s blood. The blood also contains amebocytes, that plays similar role to white blood cells in red-blooded animals. This is the material that people are looking for, and the thing that has changed the fate of this creature since its discovery.
Amebocytes from horseshoe crab blood are special ingredients for making Limulus amebocyte lysate (LAL). LAL itself is used in medical world to detect any bacterial endotoxins that have been major threats for human decades ago.
There is no other creature on this world that shares this unique trait in its blood. Thus, because of its usefulness, horseshoe crab’s blood is an A-class commodity and in a very high demand. It may explain why horseshoe crabs are being ‘harvested’.
If you don’t know about the process of extracting this animal’s blue blood, you might think that people are capturing this animal down and squeeze them to death. No, that’s not how we are extracting the blue ‘gold’ from this animal.
Indeed, fishermen are capturing this animal from the ocean floor or the shore just like they fish for crabs or lobster. But they don’t squeeze the creature to death to get the valuable blue blood. The extraction process is done by sticking stainless steel needles into their soft spot, just like how we donor our blood.
However, the amount of blood extracted from the animal is a lot more than what we used to donor. In one extraction process, about 30% of horseshoe crab’s blood is removed from the animal. The mortality rate during blood extraction is also not that big, ranging from about 3%-15% in better facilities and 10%-30% in less sophisticated ones.
It means that lack of blood caused by the harvesting is not the biggest factor in population decline. While after the extraction process, most of those horseshoe crabs are thrown back to the ocean (even though it is believed that some evil companies are not returning the horseshoe crabs to the ocean).
So, if blood extraction is not the biggest factor in the creature’s population decline, then what is? Yes, the process of sucking up the blood contributes only ‘a few’ deaths, but there is something following after the process.
Researchers believe that horseshoe crabs can survive in the wild with only 70% amount of blood left in their veins. And indeed, they have proven themselves to be that strong after decades of blue blood extraction done by human.
However, aside from the extraction stage, the handling process is believed to be the biggest cause of death. Horseshoe crabs can spend days away from the ocean before and after getting their blood extracted for medical purpose.
In addition, surviving doesn’t mean living normally. The blood extraction process may result in many negative consequences to the creature such as continuous bleeding and stress. Those are the problems that become the biggest factor in deciding the number of population here.
Both bleeding and stress can kill the creature slowly. It can take days, weeks, even months before they finally die after the blood extraction process. The slow death can fool data collecting process, since those that die of those two factors might have or have not being extracted before.
Especially for female ones, those two consequences greatly affect the breeding process. Loss of fitness and increased susceptibility to infection have also been believed to be additional factor. And this kind of process happens to about 500,000 horseshoe crabs every year.
LAL is a part of $2 billion biological safety testing market to prevent Gram-negative bacteria entering our bloodstreams from solutions and drugs injection. So, whenever a sick patient is getting an injection, the injected solution or drug must have been tested using LAL produced from extracting blue blood of horseshoe crab.
Indeed, the blue blood has saved many human lives, but how sinful and selfish we are to sacrifice the lives of a species to save our own lives. That’s why, researchers are now working on making synthetic blue blood.
In fact, synthetic blue blood has been available for about 15 years. But pharmaceutical companies are paying little to no interest in it since it is more expensive. For your information, organic blue blood costs around $35,000 to $60,000 a gallon, while the synthetic one cost a little bit higher.
In this era where the number of people reach about 7 billion, the number of people in need of injection is rising. However, the number of horseshoe crab to provide safety guarantee keeps declining. Therefore, the only option for us is to use the synthetic version.
Pushpam Kumar, the UN chief environmental economist, wrote that we are on the way to save this creature, and many others with similar fate, based on UN report that says about 30% world’s natural capital has been lost since 1972. “The report has startling findings with strong implication for conservation and development policies,” he said. Well, can we rely on the statement?