Flocke, a female polar bear plays with two of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear is seen with her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear, is seen with two of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear, is seen with two of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear, is seen with two of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear, shakes off water at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard TPX IMAGES OF THE DAY

Flocke, a female polar bear plays with two of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

Flocke, a female polar bear, plays with one of her three bear cubs born four months ago at the Marineland animal park in Antibes, France, May 6, 2020. REUTERS/Eric Gaillard

A RavnAir plane carrying tourists coming to view polar bears at the Inupiat village of Kaktovik lands on Barter Island in Kaktovik, on the North Slope, in Alaska, U.S., September 23, 2018. Picture taken September 23, 2018. REUTERS/Yereth Rosen

A float with polar bear displays is seen as members of Unidos da Tijuca samba school perform during the second night of the Carnival parade at the Sambadrome in Rio de Janeiro, Brazil, February 25, 2020. REUTERS/Sergio Moraes

A float with a polar bear display is seen as members of Unidos da Tijuca samba school perform during the second night of the Carnival parade at the Sambadrome in Rio de Janeiro, Brazil, February 25, 2020. REUTERS/Sergio Moraes

A float with polar bear displays is seen as members of Unidos da Tijuca samba school perform during the second night of the Carnival parade at the Sambadrome in Rio de Janeiro, Brazil, February 25, 2020. REUTERS/Sergio Moraes

Female polar bear Nora and its unnamed polar bear cub explore their outdoor enclosure at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020.REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020.REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

An unnamed polar bear cub explores its outdoor enclosure for the first time at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

Female polar bear Nora and its unnamed polar bear cub explore their outdoor enclosure at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

Female polar bear Nora and its unnamed polar bear cub are seen in their enclosure at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

Female polar bear Nora and its unnamed polar bear cub are seen in their enclosure at Schoenbrunn zoo in Vienna, Austria, February 13, 2020. REUTERS/Lisi Niesner

A person dressed as a polar bear attends a campaign event for Democratic 2020 U.S. presidential candidate and former vice president Joe Biden in Hudson, New Hampshire U.S., February 9, 2020. REUTERS/Carlos Barria

A person dressed as a polar bear holds a sign as Democratic 2020 U.S. presidential candidate and former vice president Joe Biden speaks during a campaign event in Hudson, New Hampshire U.S., February 9, 2020. REUTERS/Carlos Barria TPX IMAGES OF THE DAY

A climate change activist in a polar bear costume stands with New Hampshire residents and supporters of Democratic U.S. presidential candidate Pete Buttigieg waiting in the cold to see him make a campaign appearance at Elm Street Middle School in Nashua, New Hampshire, U.S. February 9, 2020. REUTERS/Jim Bourg

A polar bear plays in the water at Tierpark Zoo in Berlin, Germany January 3, 2020. REUTERS/Michele Tantussi

Polar bears play in the water in Tierpark Zoo in Berlin, Germany January 3, 2020. REUTERS/Michele Tantussi

A woman holds up a flag in the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

Two children huddle under a blanket during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A man wearing a polar bear hat puts on his shirt after participating in the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A person holds an American flag during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A man holds up a sign saying "did it" after participating in the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A woman gestures as people run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A person dressed in a Santa suit runs into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A woman wearing 2020 glasses runs in the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith TPX IMAGES OF THE DAY

People run into the Atlantic ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A person wearing a polar bear costume marches into the ocean at the start of the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A woman laughs while people run into the ocean during the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A polar bear mask is seen in the sand on the beach before the start of the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

Two men wait for the start of the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A woman wears Happy New Year glasses before the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A person dressed as the character Popeye walks on the boardwalk before the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

A woman sips champagne before the annual Polar Bear plunge at Coney Island in New York, New York, U.S., January 1, 2020. REUTERS/Stephanie Keith

People dressed as polar bears take part in a march in central Minsk, Belarus December 28, 2019. REUTERS/Vasily Fedosenko

Anti-nuclear activists stand next to men dressed as polar bears holding banners advocating for nuclear energy as a solution for climate change during the U.N. climate change conference (COP25) in Madrid, Spain, December 4, 2019. REUTERS/Susana Vera

Members of the Coney Island Polar Bear Club warm up before swimming at the beach at Coney Island in New York, December 15, 2013. Picture taken December 15, 2013. REUTERS/Eric Thayer/File Photo SEARCH "POY DECADE" FOR THIS STORY. SEARCH "REUTERS POY" FOR ALL BEST OF 2019 PACKAGES. TPX IMAGES OF THE DAY.

People walk with an activist dressed in a polar bear costume as members of the Swiss Glaciers Initiative committee hand over boxes with signatures supporting a referendum at the Federal Chancellery in Bern, Switzerland November 27, 2019. REUTERS/Denis Balibous

Greenpeace activists dressed as polar bears are seen before members of the Swiss Glaciers Initiative committee hand over boxes with signatures supporting a referendum at the Federal Chancellery in Bern, Switzerland November 27, 2019. The placard reads: "We don't have a planet B". REUTERS/Denis Balibouse