Brother and Sister polar bear match up?

There are changes afoot towards consolidating the zoo polar bear population. Some people will not be happy to lose their local polar bears. 

Wildborn Qannik and a pumpkin at the Louisville Zoo

The Species Survival Plan, which had governed the moving around of polar bears for decades, gave way about a year ago to the  Polar Bear Population Alliance, a federally coordinated effort between the AZA and the U.S. Fish and Wildlife Service (USFWS). 

Their focus has changed the way the polar bear population of 37 bears is managed, to focus on multiple bear groups, probably of one male and several females. In the past many zoos had a pair or a single bear. Now the effort aims to consolidate the population into fewer zoos, in order to facilitate breeding. Some of the zoos currently with polar bears will find themselves with empty habitats. 

Crystal nursing twin boys
 Kallik and Kallu in the Toledo Zoo.

Ten years ago, we had over 60 polar bears in the US. Now we have 37, with many of them elderly. The way things have been going, the population trend is downward fast. In addition, the gene pool has been shrinking and now we have a majority of the younger bears descended from Crystal (and except for the last set of twins, father Marty).

Certain laws don't allow Canada to send their rescued cubs to any other country. And the US has a law that doesn't allow any polar bears to come into our country. Crystal came from Belgium, but that was before the prohibition law was passed in 2008. In fact we used to trade bears back and forth with Europe. The two older ladies in San Diego were Canadian rescue cubs.

Wildborn Kali at the Detroit Zoo

There has been one victory, that the Department of Fish and Wildlife now allows rescued Alaskan cubs to be part of the breeding program. This affects females Qannik in Louisville, Kava in the Alaska Zoo, and the male Kali now in Detroit. Fresh genes, if all goes well.

We have two male proven breeders, Lee and Nuka. Lee is in Columbus with Aurora, and there may very well be cubs from that pairing this year. They are already the parents of Kulu, who is now in the Como Zoo. 

Lee at the window, Aurora on shore in Columbus.

Meanwhile, proven breeder Nuka is in Toledo with elderly Crystal, who is likely too old and deserves a quiet retirement. Even if Crystal were to have cubs, it would be yet more Crystal offspring. Maybe Nuka would be better paired with a daughter or granddaughter of Crystal. Nuka also has a twin brother Koda who languishes alone in Memphis. I don't understand this. 

Nuka, when he was in Detroit. Suka and daughter Astra in foreground.

There is a lot of discussion about the most recent match being made between half brother/sister uncle/niece in the US. That is the bringing together of Laerke, currently in Tacoma, and Kallu, who is in St. Louis. Laerke and Kallu have the same father, Nuka, and Kallu's mother is grandmother to Laerke, so very closely related on both sides.

Baby Kallu, with his mother Crystal, in Toledo

Laerke is also a rather special bear, with some health concerns, and is very tiny at only 400 pounds. She was raised by keepers, as she was quite frail at birth and needed a lot of extra care just to keep her alive. She had a grizzly cub companion Jebbie as a childhood companion.

Laerke as a cub in Detroit

Jebbie and Laerke as playful cubs.

Twin sisters Astra (back) and Laerke in Detroit.

 We already have several situations with related bears: Hope is with her Uncle Hudson in Brookfield. Neva is with Nikita, who is half brother to Neva's mother in Hogle Zoo. Astra and Kulu are first cousins in Como Zoo, their mothers Suka and Aurora are sisters. It is getting more and more tricky to find suitable mates with the limited gene pool.  

Family ties

I thought I would look into several of the interesting inbreeding situations that have happened in Europe. These match-ups were not intentional, but they did produce offspring.

Hertha as a cub in Tierpark Berlin

Little girl Hertha was born December 1, 2018, in Tierpark Berlin to Russian born pair Tonja and Wolodja. 

Hertha and mother Tonja

It was discovered after the birth of Hertha, when both parents were genetically tested, that Tonja and Wolodja were both offspring of Simona and Wrangel in the Moscow Zoo. In the year Tonja was born, Murma also gave birth in the Moscow Zoo, and due to "clerical errors" (sloppy recordkeeping) on the part of the Russians, Tonja's records were swapped with another cub. So Tonja and Wolodja were brother and sister. There were suspicions of this when Wolodja first was sent to Berlin, but some corrections were made in the studbook and everyone was assured that they were not related.

Wolodja

After DNA tests showed that Wolodja and Tonja were siblings, Wolodja was sent to another zoo, while mother Tonja raised her daughter Hertha at Tierpark Berlin, and there they both are to this day. Both Tonja and Hertha were put on the "do not breed" list.  Hertha seems to be perfectly healthy and happy. She was even the subject of a story in People Magazine, with adorable phots.

However, there were some dark days at Tierpark Berlin in the years before Hertha was born.

November 3, 2016, Tonja gave birth to twins, with the girl dying in days. Hopes were high for the surviving cub. Fritz, yes he lived long enough to gain a name and many cute photos in the news. But in a matter of just a few days, mid March 2017 at age 4 1/2 months, Fritz sickened and died of multiple organ failure and hepatitis. 

 In December of 2017, Tonja again gave birth again, with the girl living for 26 days before passing away. 

Tonja and Hertha play 

Berlin rejoiced again with the birth of Hertha, but questions, which had arisen when Wolodja first arrived from Moscow, surfaced again. The DNA tests were done, and it was shown that Wolodja and Tonja were brother and sister. The European zoo association said that they would not allow a situation in which adult brother and sister would be together, so Wolodja was moved to the Netherlands. He is currently in Rotterdam, with another male bear.

Polar bear cubs, in zoos and in the wild, have a 50 percent mortality rate, and this may explain the fate of the earlier cubs, but we will never know. 

Yoghi in Munich

Yoghi and son Blizzard

Yoghi was born in 1999 to Bimba and Romeo in Pistoia Italy. His father Romeo was also the father of Bimba. 

Blizzard in Hamburg

And then there was a second incident of inbreeding in this same family in that Italian zoo. In 2006, Bimba gave birth to Blizzard, with Bimba's son Yoghi as the father. So Blizzard was the product  of two generations of parental inbreeding. Blizzard spent many years in Hamburg, never fathering a cub with Victoria, so he was tested and found infertile. Was this a result of inbreeding? We don't know.

Yoghi went on to father three more cubs with a female bear who was NOT his mother. Giovanna and Yoghi became parents of beloved Nobby and Nela in in 2013, and Quintana in 2016.   

Ballyba

Ballyba, who was born in 1990 in Aalborg Zoo in Denmark, and at almost 36 is now considered the oldest polar bear in the world, living in Japan, She was the offspring of father Miki, and Miki's own daughter Nuka II. Ballyba has one daughter, Peace, but Ballyba declined to raise her, so the keepers took over. Obviously, having some inbreeding in her background did not affect Ballyba's longevity. She is reported to be in good health for her age. 

Ballyba's sister Malik nursing Nuka and Qilak
(father was Lars) in 2017.

 Ballyba is sister of Malik still in Aalborg, born ten years later. The inbreeding mistake was avoided this time. Ballyba and Malik share the same mother Nuka II but Malik's father was unrelated Nanok.

In the earlier days of polar bear keeping, breeding was haphazard and not kept track of very well. And zoos housed many more polar bears, often with males and females all kept together, with no one keeping track of parentage. 

Currently, much more care is taken. All the bears are recorded in a studbook, and matches are supposedly thoughtfully arranged. Young cubs can be identified with sub-dermal chips. And there are a lot fewer polar bears to keep track of.

Astra and Kulu of Como Zoo

 

Astra with some watermelon
 and a coconut hidden inside the watermelon

At Como Zoo in St. Paul Minnesota, there lives a young polar bear couple who may be in the family way. Although they are very young (Kulu will be 7 this fall, and Astra will be 6 years old), there was some breeding last spring, so many are hopeful.

No cubs were born in the US last year, or the year before. In fact the most recent cubs, twin boys Kallik and Kallu, were born to Crystal and Nuka in Toledo on November 11, 2022.

Kulu and Astra in November, 2025,
getting along just fine.
Photo by my daughter Corinna Troth

Astra and her twin sister Laerke were born in Detroit to Suka and Nuka on November 17 2020. Laerke was raised by keepers, due to health issues, but the girls were reunited and went to Point Defiance Zoo together, for a time, then a year ago, Astra came to Como Zoo to meet Kulu, and they got along very well. 

Kulu a few weeks ago, separated from Astra.  

Kulu was born to Aurora and Lee in the Columbus Zoo on November 28. 2019. He was a single cub, so played with his mom a lot, and also with his Aunt Anana. He came to Como Zoo in 2021.

Kulu's mother Aurora and Astra's mother Suka are sisters, both are daughters of Crystal and the late Marty. Kulu's father Lee and his twin sister Anana were born in the Seneca Park Zoo to Rochester Aurora and Yukon (who was born in the Cincinnati Zoo). Suka's father Nuka and his twin brother Koda were born in Denver to Voda and Kavik. 

Astra and her beautiful reflection

There was quite a bit of amorous activity in the spring, and the two played together all summer. Now Kulu misses his girl. She has been separated from him, confined to the deep pool side, in preparation for denning up, which I am told will happen October 12. Reportedly, she has gain quite a bit of weight, which is a good sign, but not a sure sign.

Some lettuce for Astra

Getting some exercise before denning up,
Astra strolls around the right hand enclosure

In the center demonstration area,
 Kulu peers out the window at Astra,
and bangs on the door.
He misses his playmate.

Old Neil on the left, Kulu on the right, in the lefthand enclosure

Kulu walks by Polar Bear Rock

Astra has a secret smile about something, 

Kulu chasing around Astra last November.
 (Photo by Corinna Troth)

 There are no pregnancy tests for polar bears, and we will know the result when she has cubs or not, which is usually in November or December.

Suka and Haley, the Ladies of Detroit

 

                    Suka and Haley looking for snacks in the Tundra area.

                      Hey Suka, there's an apple in the crack in the wall. 

We have three polar bears at the Detroit Zoo these days: the male Kali, and the girls, Suka and Haley. 

Haley and Suka on the Pack Ice side of the Arctic Ring of Life.

Haley with a carrot, in the underwater tunnel viewing area.

Haley and Suka are about the same size, and similar fur.

Haley's paws are spotty and mostly pink. 

 You can tell them apart when they are in the viewing tunnel, for Haley has lack of pigment in her paw pads. 

Haley swims laps in the left hand corner
of the underwater viewing area.

 Haley also swims a particular recognizable lap, that Suka 

does not. Plus, if you see one of the girls approaching Kali, it is probably Haley. 

Suka in the right hand corner of the underwater viewing area.

Suka has been there the longest, since. 2018. She was born on November 21, 2012, in the Toledo Zoo, along with her twin brother Sakari, who is now in Buffalo. Their parents are Crystal and the late Marty. 

Suka and Sakari as cubs in Toledo.

The twins moved to Como Zoo in St. Paul in 2014 for about six months, while the new polar bear enclosure in Henry Vilas Zoo in Madison Wisconsin was being finished.

Suka (front) and Sakari in 2015 in Henry Vilas. 

Sakari moved out first, going to Buffalo as a mate for Luna (same Luna Kali lived with as a cub), but Suka stayed at Henry Vilas for three years, sharing space with older lady Berit for a time. In 2018 Suka moved to Detroit, and in 2020 she gave birth to twin girls, Astra and Laerke. 

Astra and Suka in 2021

Nuka across the way, with Suka and Astra in 2021 in Detroit.

Grizzly cub Jebbie came to Detroit as companion for Laerke,
who was being raised by keepers.

Nuka, now in Toledo, is father of the twin girls born in Detroit. Their mother Suka will be 14 years old this fall.

Haley in 2012 in Memphis.

Haley was born in Seneca Park Zoo in Rochester NY to Aurora and Yukon, on November 15, 2002, the last of their four cubs.  In 2005 she moved to Brookfield Zoo to become acquainted with Peyton, a young male there, and together they moved to Memphis in 2006, but never did produce cubs. She moved to Detroit in March of 2025. She will be 24 years old this fall, a little old to be having her first cubs, but we remain hopeful.

Kali, the current male at the Detroit Zoo, was rescued as an orphan in Alaska, and spent his first two years at the Buffalo Zoo being companion to Luna of the same age.

Kali as a just rescued Alaskan cub in the Buffalo Zoo in 2015.

Kali lived alone in St. Louis for a decade before coming to the Toledo Zoo for a short stay and very little romance, and then to the Detroit Zoo where it is hoped he will be more successful with these two lady bears.

Kali in 2016 in the St. Louis Zoo. 

Kali in Detroit

Suka's mother Crystal, the older lady bear in Toledo, did not like 12 year old unsocialized Kali. Everyone knew she liked Nuka very well, as they had lived happily together and produced twin cubs, so the two male bears, Nuka and Kali,  traded places at the beginning of 2026.

Haley in her corner, Kali watches her from atop the tube in the underwater viewing area. 

At first it was a rocky relationship between the two Detroit girls and the new guy, as Kali had not spent a great deal of time with other bears. He had grown up with Luna in the Buffalo Zoo at the beginning, that was a long time ago, and after he moved to the St. Louis Zoo,  he was all alone for over a decade so as an adult, he had not known another bear. Kali didn't know how to live together with the girls. 

There was some breeding going on early in the year with both lady bears during breeding season, but Kali was definitely an amateur, and needed more practice. It is doubtful that either Suka or Haley is pregnant, but we can hope. Next year, he will know better what he is doing. In any case, the Detroit Zoo is currently building a second den for Haley. Both girls will be denned up this fall, just in case.

In July, Haley in front, Kali at a distance.
She tries to make friends with him. 

After breeding season, Suka has been doing her best to avoid Kali. Haley has made him her project, however, trying to socialize him. 

Suka and Haley in the Tundra area of the Arctic Ring of Life in Detroit.

Haley and Suka in the Pack Ice part of the 4 acre polar bear habitat.

Haley wearing the tube. Note her paw coloration. 

The girls swim their underwater ballet together,
using a tube for even more fun.

Haley loves to swim in the Detroit pool.
 In Memphis, she did not have a deep pool with all the
 caves and pillars for hiding. This is great fun for her. 

Suka went diving and found a piece of melon.

We will be watching to see how Kali's social skills improve as Haley teaches him how to be a successful male bear in a relationship with two lady bears.

We will also be watching to see if the outside chance for a cub in Detroit comes true this spring.