This is the story of the fabric of life, and how every species is interconnected – each one important, no matter how big or small. At its center is the humble horseshoe crab, a creature which has remained virtually unchanged for 350 million years. Its annual spring spawning produces millions of eggs that are the lifeline for a tiny bird called the red knot, which migrates 10,000 miles from South America to the Arctic each year. Scientific and medical communities have discovered that the crab also provides an indispensable testing agent for drugs and vaccines, as well as resources for human optics and burn treatment. But horseshoe crab numbers are plummeting from their new use as bait for the fishing industry, dropping by two-thirds or more since 1990. And the precious pyramid depending on this age-old creature is about to come crashing down. Filmed and presented on television in high definition.
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This program premiered February 2008.




(40 votes)

Thank you for making this film and I hope lots of people watch this film. Education and understanding is the key to bring back eco balance which we humans destroying nature in everywhere.
It may be a small bird but what a champion it is and we could learn so much from its physiology and enduring capabilities and learn to live in harmony with our environment instead of continuous exploitation. I hope this has a happy ending. Thank you for providing an invaluable video to provide education for our next generation.
It’s too bad that we are at the top of the food chain and most of us don’t give a damn. What came first, us or the horse shoe crab? Who will finish last?
From nature comes man, from man becomes nature. Conservation.
Thank you for this film.
Thank you for making and airing this film. I think it’s monstrous for us to bring such an ancient creature this close to extinction. For an animal that survived not just one massive extinction but two, and was thriving long before we came along, it’s a pitty that humans are worse than events that killed over 95% of life on Earth.
I hope that we have a nuclear war, so that we can
destroy ourselves and leave this beautiful planet
alone.We don’t deserve to live here.I can no longer
watch a nature show that doesn’t tell me that an
animal or habitat has been destroyed,is being
destroyed, or will be destroyed by us.Any animal
and plant that survived a nuclear clearance would
do much better than us at taking care of this
special earth.
why doesn’t someone lab raise the horseshoe crab at least until it is two or three years old? and if they are going to catch the birds and put them through that much stress then why not feed them while they have them in their possession? Also, if they are going to catch a portion of the birds, study and then release them why don’t they keep the birds that are underweight and make sure that they don’t die on the trip up there?
Hmmm. A nuclear war that destroys wildlife, habitat, children, and about all else. That’d solve a lot. Methinks education would go a long way…
Although Nature has always made an effort to educate, the reactions sometimes show it to be insufficient in that regard.
Education would be the best, but when all interest are to continue to play GOD on the planet in every aspect of life, to rule via power and deceit it is ineveitable for man to destroy. As a Natural Resource major we can only count the days and months until Easter Island is once more. Education cotinually wants us to analyze history but we chose not to learn from it! Greed is always there to rape and pilfer, and at the same time we as humans look at only what can I do to fix it now. We chose not to look at what will fix the future, the basics of our needs to survive like our ancestors is food, shelter and water. Salinity is on the increase in farmlands, acidification, and global warming in increasing, etc…when do we stop and look at the overall picture that we do not have the right to play GOD….we are the stewards and we are not do a good job.
Thanks for this enlightening film.It’s too bad such fine efforts are still necessary. What I mean is, though extremely educational, and entertaining, it was only in the early 90’s that the issue was fully understood and any short term action was quickly
they talk about extinction on television..but this story really grabs you by the heart (as one from maryland). To much damage….to little time..
very moving
First of all, thank you for this wonderful series. I love you and PBS. I appreciate that you give the various sides of a situation, but though I understand the reason for our dependence on the Horshoe Crab it was disturbing to see how they were treated in the lab. They look to be piled one on top of the other in laundry baskets, dipped and sprayed in some solutions–probably to be sanitized–strapped over their eyes and inserted with large needles to be bled. The narrator stated 18% die, but could it be higher? Afterwards they’re piled together after they’ve contributed to our well being. Has anybody observed these procedures, to understand why they are dying and where–in the lab or when they are being sent back for release? Could a more ethical way be considered? If a sentient being can’t cry out in fear or pain we don’t seem to connect the dots. Isn’t that why scientists and environmentalists are sounding the alarm on behalf of those who can’t? I believe that we can.
This show is so neat, in fact it’s on right now. I try to watch Nature every Saturday and this is my favorite episode. I can sit and watch Nature all day. I really enjoyed the life of the horsesho crab. And the red knot’s migration. It would be interesting to work with animals. Thank you for such an educational show.
This episode greatly upset me. Not only because of the loss of species, but because the writers perpetuated the same outlook as those who caused such devastation–that the horseshoe crab is useful to people, and therefore its okay to treat them as a commodity. Unlike the excellent Frogs episode, where conservation was for its own sake, conservation of the crabs was portrayed as a means to an end. The end of course being more medical use and more food for the birds (though of course conserving the birds was never justified in that way). One can only assume this narration was written in such a way because the horseshoe crab is perceived to be a creepy looking creature instead of cute. The positive spin on the bleeding of crabs made me sick to my stomach. Can you imagine if they tried that argument with the red knot birds?
I sincerely hope upcoming epsiodes don’t follow this disturbing trend, otherwise there is really no hope for conservation of unusual looking creatures.
Thank you for TV that captivates and educates the mind. I believe that you lead many to aspire to a better way for themselves and the planet. My hope is that your efforts will be the salvation of the beautiful red knot, and its partner in nature, the horseshoe crab.
Compelling episode – congratulations to the filmmakers and to all involved with conservation. As a wildlife photographer and lifelong birder and sailor, this was eye-opening even for me. I took horseshoe crabs and red knots for granted – they’ve been there in numbers all my life. As a teacher, I took the lesson I learned from this and passed it on to my students.
On a recent shoot in Florida, I found a banded bird at the Atlantic shore and immediately reported it to the Delaware/NJ people. I always report banded birds no matter where in the world I am, but it took on a new urgency after this episode.
Wonderful, wonderful job.
Kudos to all!
american people r responseble 4 destroing the world beauty they are the most polutet country & war moarte va urez la toti din sua
Hi from Oregon. Recently (within the past 8 years) the largest salmon fishkill in recorded human history took place on the Klamath River just south of the Oregon/California border. This was directly due to actions taken by the residents of Klamath Falls (a city) and environs when they took action (with the assistance of the Bush II administration) which resulted in an extremely low river flow downstream. This single act decimated a population of fish which had been feeding tribes along the river for centuries, possibly several millennium. The Klamath Falls farmer’s response to the outcry which I remember most vividly: “who cares, it’s just one fish”. This was said directly to the face of a Native American whose livelihood had been destroyed.
There is every likelihood that dead zones off the coast of Oregon are due to the runoff of nitrogen from agricultural practices which are still common within the state. Again, we are hearing “it’s just some fish, who cares” from those who are the most likely cause.
I used to live in Klamath Falls. I have also lived in the Willamette Valley region – another agricultural stronghold in Oregon and the region most likely to be causing the dead zones – for much of my life. I don’t think that nuclear war or any war will solve the problem as typically war renders the environment unlivable for anything, not just humans. War is a sum of arrogance and willfull stupidity, not a resolution thereunto. Instead, entreat the arrogant, talk to them, pursue their arguments to the logical end. One may not have the answers, but one can certainly elucidate the questions. Call your politicians and THREATEN them with being fired at the next round of elections, then work to follow through on the threat if they fail to follow through on protecting our only home. We should consider slowing this nation down a bit; we over-consume, over-produce, seek constant economic growth and demand that our trading partners follow in lockstep with our consumptive ways. In the last 40 years we have evolved our nation into one where the vast majority of households with children have to be dual earner households just to stay afloat above the poverty line; just to feed, clothe and house our children.
Understand that family farmers in the Willamette Valley and the Klamath Falls are “feeling the pinch” of the economy just like most of us are. The difference is that they always feel the pinch because farming has always been a hit or miss proposition, so they feel compelled to do whatever is necessary to protect their livelihood. Perhaps if we were to try to live by the axiom that “less is more” we might be able to survive until the next century, though I am not hopeful frankly. Less is more… Less is more… Less is more… Oh, and cotton is a terrible choice for textiles, it leaches the soil and demands more fertilization than any other crop – fiber grade hemp is a far better choice as it lasts longer, requires no fertilization in most agricultural regions and is proved to actually return nitrogen to and fix carbon in the soil. Less is more… Grow hemp for industry… Be a patriot and work for the future of your country, not the now of your wants. Pardon me, I have to go now, Zarathustra calls…
[...] I picked this video because it shows alot about them Tale of Two Species [...]
What sad is that everyone hates on humans for destroying environments. Yes we have done some unjust things to our planet, more or else associated corporate doings. Most humans show more than enough consideration to our fair planet. As in all life, we as humans are also beautiful creatures and wonderful beings to behold. So dont mock us for surviving in a world that has no laws or rules on lifes path. Just to survive in it is great enough. We can nurture the environments of life much better when the corporations are gone.
[...] how important this species is to life as we know it. We watched a great PBS video before we went (watch it here). [...]
[...] you’re interested in learning more, here’s a great PBS film: "Crash: A Tale of Two Species" Oh, and if you ever find yourself walking on a beach and happen upon a horseshoe crab upside [...]
This program was not only educational, but also so beautifully made that it moved me to tears. The scientists deserve praise for their efforts to understand and sustain these creatures, as do the journalists who shared this story with the public.
i enjoyed this film very much, very educational…didnt realize the horseshoe crab played such a huge role to humans. If only everyone knew our plant really does survive on such a delicate line and once undone can be catisrophic for all specices … sorry for the spelling eyesight is blurry
This was a really well done piece about two creatures seldom thought of, and taken for granted by so many. Those of you involved with helping “thank you”. And I also was unaware of the HS crab’s role in human health. I’m sure the rabbits appreciate them!
this really proves how delcate the ecosystem is
This movie has inspired a large number of my students. What a gift it is to make it available in this way!
Jim Forde :-)
Scofield Magnet MS
A lot of people don’t give a damn what we do. We better protect where we live or else one day the food chain my break…
I really love this video. My students all loved this video. We made a class project about it. It was absolutely lovely. Thank You.