With each passing year the Discovery Channel's celebration of all things chondrichthyan has become interwoven more and more with the conservation of our cartilaginous fishes: sharks, skates, rays and chimeras.

And with good reason. This amazing class of fishes, which includes as many as 1,250 species, have swum in the oceans of our planet for more than 400 million years.

Yet they are disappearing. Overfishing to supply global markets for meat, oil, leather, fins, curios and other products has eliminated many shark and ray species from portions of their range. Demand for shark fin soup – a Chinese delicacy – has had an especially devastating impact on shark populations in recent history, but is now being matched by global demand for shark meat.

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We need to address this crisis now before this globally important group of animals vanishes from our seas. That is why members of the marine conservation community cheered the introduction recently of the Shark Fin Trade Elimination Act of 2016, sponsored in the U.S. Senate by Sens. Corey Booker (D-NJ) and Shelley Moore Capito (R-WV) and in the House by U.S. Reps. Gregorio Kilili Camacho Sablan (I- Northern Mariana Islands) and Ed Royce (R-CA).

Legislation is sorely needed to reduce the United States' contribution to the collapse of shark and ray populations around the world.

A recent analysis of sharks and rays conservation status by the International Union for the Conservation (IUCN) Shark Specialist Group found that close to a quarter of chondrichthyan species are likely threatened with extinction. Nevertheless, inadequate regulation of fisheries at both the national and international levels continues to represent a great threat to sharks and rays.

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This is of particular concern due to the late maturity and generally long gestation periods of these fish. For instance, gracefully gliding manta rays -- with wingspans seven meters long -- give birth to only one live pup every two to three years. This makes sharks and rays especially vulnerable to overfishing and slow to recover.

The Global Sharks and Rays Initiative (GSRI) has identified 40 priority countries based on shark and ray landings by volume. Top exporters include Argentina, Indonesia, Spain, New Zealand and the USA, among others.

Some currently manage shark and ray fishing and promote fisheries reform. Others lack the capacity or resist fishing limits due to opposition from the commercial sector.

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The decline and disappearance of sharks and rays is both a biodiversity loss and a threat to the livelihoods of the fishers and other users, including the dive tourism industry, for whom these species are a resource.

In 2013, the 178 government members of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) agreed to regulate the trade in several seven sought-after shark and ray species, including the mantas. The support of so many countries marked a milestone for sharks and for marine conservation more generally.

This fall, conservationists will reconvene at another global CITES meeting in Johannesburg, South Africa. WCS and many of its partners will be supporting proposals to include silky and thresher sharks, along with devil rays and ocellate river stingrays, in CITES Appendix II.

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Appendix II includes species that although currently not threatened with extinction, may become so without trade controls, as well as species that resemble those to minimize such trade.

In the meantime, the global community must commit the resources -- political, technical, and financial -- to safeguard the future of sharks and rays. That means adopting laws and regulations specific to these fishes, putting in place trade controls and fisheries management measures and effective monitoring, engaging fishers and other users, as well as initiating species recovery efforts.

Here in the United States, the legislation introduced by Sen. Booker and his colleagues can help to shed light on the plight of sharks and rays by addressing one of the key threats to these species globally.

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We look forward to continue building on this legislation to ensure that we address the broad array of threats faced by these fishes that have captured the imagination of so many.

Shark Week is an opportunity to remind our elected leaders that the U.S. must strengthen its leadership in improving the management of shark and ray populations globally. But it is also a time to remember that we must be better caretakers of the natural world around us.

And while Shark Week may provide the opportunity to revisit Steven Spielberg's classic film about a certain great white shark terrifying a quaint New England beach community, keep this in mind:

We can always get a bigger boat. There's only one planet earth.

John F. Calvelli, @JohnCalvelli, is Executive Vice President for Public Affairs at WCS (Wildlife Conservation Society).