The defeat came at an extraordinary gathering in Bremerhaven, Germany, of the intergovernmental Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR, pronounced kam-lahr), which concluded without an agreement.
It marked only the second time that the 32-year-old CCAMLR has convened outside its annual meeting.
The session was called after China, Russia, and Ukraine opposed other members to defeat Antarctic protection plans at the 2012 CCAMLR meeting.
The two separate plans for Marine Protected Areas (MPAs) would ban fishing and other potentially harmful activities in around 3.5 million square kilometers of sea off the Antarctic continent.
Conservationists regard such protection as an overdue step to protect a delicate region that plays an oversize role in global climate and ocean health.
Opponents have defended fishing rights and challenged the scientific basis for the sanctuary plans -- one by a U.S.-led initiative and the other spearheaded by the European Union and Australia.
Andrea Kavanagh, director of the Pew Charitable Trusts' Southern Ocean sanctuaries program, participated in the Bremerhaven talks. She told RFE/RL's Eugen Tomiuc that Russia questioned the legal right of CCAMLR to declare such sanctuaries.
"Russia asked for this special meeting at Bremerhaven back in Hobart in 2012 to talk about science. So CCAMLR agreed and, at great expense, all countries and the CCAMLR secretariat flew here to Bremerhaven to talk about the science behind these proposals, which the scientific community was very clearly supportive of," Kavanagh said.
"So for Russia to come out then, and say now that they have some legal objection was a complete shock and, frankly, viewed as a delaying tactic by most people."
It was not immediately clear whether backers of the Antarctic protected areas would seek new debate on the proposals at CCAMLR's next annual meeting in Hobart, Australia.
Kavanagh said Russia would have to explain why it scuppered the talks on July 16. "The next step in this process is that there will be some high-level diplomatic reach to the Russians to hopefully put to rest this notion that CCAMLR does not have a legal mandate and then get them to talk about their specific objections or [what their] requirements are for these MPAs to go ahead," she added.
"Now, until Russia is willing to actually say what they want on a detailed concrete level, no one is going to negotiate with them."
The Antarctic Ocean Alliance (AOA) described the Russian block on the July vote as "the loss of an extraordinary opportunity."
Antarctic Marine Reserve Talks Fail; Russian Delegation Stalls Progress#CCAMLR— pew environment (@pewenvironment) July 16, 2013
Russia, Ukraine In Lone Opposition
Reports suggested that Asian objections had eased since the November meeting, leaving Russia and Ukraine as the lone holdouts against the MPAs. Kavanagh told "USA Today" that Russia was "the big unknown" ahead of this week's meeting.
The advocacy group Ocean Elders, in an open letter to Vladimir Putin, had urged the Russian president to back the sanctuaries and exercise Moscow's "critical leadership role...in determining the future of Antarctica."
The signatories -- who include British entrepreneur Sir Richard Branson; Jean-Michel Cousteau, the first son of the late French ocean explorer Jacques Cousteau; and Canadian filmmaker-explorer James Cameron -- urged passage to "reaffirm the leadership of CCAMLR member countries on marine conservation of the high seas and leave a substantial legacy for future generations."
On the first day of the German meeting, Moscow challenged CCAMLR's legal authority to create MPAs in the Southern Ocean, Inter Press Service and Reuters reported, quoting German and Norwegian sources and a leaked recording from the closed-door proceedings. Kyiv reportedly joined the Russian objection.
Critics note that Russia's agreement two years ago to an MPA near the South Orkney Islands appeared to undermine its argument.
Ukraine's delegation meanwhile had suggested that fishing was the best way to monitor the health and strength of fish stocks in Antarctica. That argument is reminiscent of Japan's claims that its continued "scientific whaling," despite a global ban, provides valuable research.
The WWF has pointed out the essential role of the Southern Ocean in the food chain, particularly as a source of krill, the tiny crustacean that feeds whales, penguins, and seals, among other animals:
An effective counter needs to be developed against countries that view the region largely as a new fishery and will oppose effective implementation of conservation measures. Illegal, unregulated and unreported (IUU) fisheries also remain a significant threat and need to be addressed through international law, port-state controls, surveillance, and enforcement.
The proposed sites for the MPAs under consideration -- in the Ross Sea and East Antarctica -- are of special interest because they have been spared the worst manmade damage and are home or feeding grounds to significant populations of whales, seals, and seabirds, including penguins.
The proposal before CCAMLR from the United States and New Zealand would create the world's single largest MPA, banning fishing and hunting throughout more than 2 million square kilometers of the Ross Sea south of the Pacific Ocean. The U.S. State Department in a statement called the Ross Sea region "one of the last and greatest ocean wilderness areas on the planet."
The other proposal, by the European Union, France, and Australia, would set aside seven smaller MPAs of a combined 1.9 million square kilometers "to protect representative areas of open ocean and seabed biodiversity in East Antarctica," near where the Southern Ocean meets the Indian Ocean.
Each of CCAMLR's decisions must be unanimous among the group's 25 members.
Scientists agree that the earth's poles are crucial for enriching, circulating, and filtering ocean waters, as well as nurturing some of the most basic building blocks of the global food chain and cooling the planet.
WATCH: A Pew Charitable Trusts video arguing for passage of greater protections for Antarctica's Southern Ocean:
The Antarctic has seen increasing threats to its health, including from overfishing, climate change, and mounting pollution.
The Southern Sea is home to an estimated 10,000 "unique species" that are not thought to exist anywhere else in the world.
The proposals have broad support among environmental and ecological groups, although many suggest they stop short of the proactive role that was envisaged when CCAMLR was created in 1982 under the international Antarctic Treaty System.
UN Secretary-General Ban Ki-moon has set a goal of conserving "at least 10 percent of coastal and marine areas" by 2020.
The world's current total of marine sanctuaries represents less than 2 percent of the oceans.
-- Andy Heil