After two decades of calamity and conservation, what’s comes next?
Following this opening blog, I wrote five more to help figure out the state of the Delaware Bay Shorebird Stopover. In this internationally recognized critical habitat, red knots and five other shorebird species rebuild themselves after a 5 thousand mile nonstop flight from South America. They need fat to fuel the next leg of their journey into the depths of the Arctic. Did the birds leave Delaware Bay in good condition? While in the Bay, the birds gorge on eggs laid by horseshoe crabs deep into the Bay’s sandy beaches. Did females crabs spawn in sufficient numbers to support knots and other shorebird species? Over the last six years, we have restored bay beaches with new sand lost to storms. How did beaches fare after a year of winter storms and other threats? Did the changing climate and rising waters reshape the shoreline of Delaware Bay? These questions loom large for all the people who care and try to restore the Bay’s resources. I explore them in this series of blogs.
Red knots roost near Reeds Beach NJ along the north shore of Delaware Bay
Devastation and a lackluster response
After a devastating overharvest in the 1990s and a lackluster decades-long effort to overcome it, still too many crabs die every year. Too many businesses make money by killing crabs without doing anything to replace them. They strangle recovery while enriching themselves.
The agency in charge says they can do no more and their path to recovery is well worn and unlikely to succeed in our lifetimes. Is that all that can be done?
Yes if we only let experts decide.
No, if we reshape our conservation. In fact, a path exists that can lead us to a remarkable ecological transformation. If we stopped the killing of horseshoe crabs, recovery would come in less than 15 years migrant shorebird numbers would grow. better yet so would the bay’s productive base. Eggs and hatched young would flow into the bay’s fertile sea. Productivity would skyrocket. Sportfish, like weakfish, flounder and stripers could rebound from their own depleted condition. The bay would once again become the ecological cornucopia of the past.
Getting there requires expanding the coalition of people who care. Until now the battle to protect horseshoe crabs rested on the needs of red knots and other shorebirds. For too long, we emphasized the decline of the shorebird stopover because fishers overharvested crabs. This forced too many shorebirds into a mortal competition for too few crab eggs. The red knot, in particular, takes center stage in this fight to restore crabs to their original number, at least three times that of today. Although our emphasis was well placed, it still missed the mark for much of the concerned public.
Horseshoe crabs provide essential support for nearly every fish species in the bay
Because we failed to focus attention on the larger impact on the Delaware Bay ecosystem. Nearly every species of fish breeding in the Delaware Bay uses horseshoe crabs eggs or hatched young. Forage fish, like killifish and silversides, eat crab eggs and larvae and in so doing become part of the food chain underpinning the sport fishery of the bay. Young fish, like the iconic weakfish, feast on eggs and the hatched young. This spigot of productivity fed fish during their own breeding season.
Unfortunately, we closed the spigot when fishers overharvested horseshoe crabs. The current lack of eggs and larvae may be the defining reason why nearly all sportfish in the Bay’s ecosystem suffer. The agencies have a name for it – economic extinction, that point when the effort to catch fish no longer warrants the costs.
Sea turtles and shorebirds depend on horseshoe crabs
Surprisingly few people know juvenile loggerhead turtles as old as 18 years old, prefer horseshoe crabs more than any other prey. Or that they concentrate in Delaware Bay for months. Jim Spotila of Drexel University surveyed them in 1997 and found that Delaware bay hosts more than any other estuary in the east coast. Joe Smith, Stephanie Feigin and I flew the bay this August to replicate Jim’s survey and found at least 9 in a very small sliver of the total area of the bay. Kemps Ridley turtles also use the bay’s horseshoe crabs. Both endure range-wide threats justifying Federal Endangered status. No agency or scientist knows the impacts of overharvesting horseshoe crabs on Delaware Bay’s sea turtle population but as with forage fish, we risked it all on the needs of a few fishers.
And of course, the most well-known victim of this ecological tragedy is the sad story of shorebirds. Each year they travel thousands of miles to reach Delaware Bay unaware of the horseshoe crab crapshoot that awaits them. In some years too many birds found too few horseshoe crab eggs to recover from their arduous flight and rebuild for the next leg. In those years many shorebirds died.
Thus one can envisage how the largesse of horseshoe crab eggs seen in the above 1986 video turns into fish, birds, and turtles. These resources attract fishers, birders, and tourists. In turn, these users create real value to the many businesses that cater to their needs: marinas, bait shops, restaurants, hotels. Now in this relative absence of the abundance, few marinas remain profitable and both restaurants and hotels struggle to exist or are lost already.
So Why Kill Crabs?
With these substantial economic impacts, why do we kill crabs for bait when other baits exist? Why do international biomedical companies carelessly bleed crabs killing hundreds of thousands in the process? Why do both groups pay no price for the damage they cause to a resource owned by the public? Given all this why do agencies allow them to keep coming back for more!
I try to answer these questions in the following blogs. To do that I try to feel the pulse of the stopover and crab population. I explore how and why the agencies give priority to the industry while requiring nothing in return. What other losses remain unaccounted? Why not attempt full restoration as fast as practicable?
Most importantly how do we provide our children and their children the same natural bounty we have squandered but could easily restore? This question focuses on my five blogs. And here is the simple answer. Stop killing horseshoe crabs.
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