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.

Nuka entertains his fans in Toledo

Nuka seems to be a happy fellow.

21 year old Nuka knows he's a popular fellow, and is happy to see his fans when they come to visit him in the Toledo Zoo. Especially because Ice Queen Crystal has chosen to remain behind the scenes for most of the summer, only making rare appearances.

I visited Nuka a few weeks ago in Toledo. On both days I was there, he was out and about, greeting the visitors, strolling about and swimming. Crystal remained hidden.

During my Toledo visit, Nuka came over to one of the windows where I was waiting with my camera, and posed quite deliberately for me, looking me right in the eye. Maybe he remembered me from my visits to Detroit?

My private moment with Nuka

Gazing into my camera lens.

A little smile from Nuka

 One of the employees showed me a photo of Crystal taken the night before, as she had come out during a Friday night private event but only napped in the den. Crystal has the choice of coming out. The people who know her, the employees, say she will probably come out more often in the fall, when cooler weather returns. 

Nuka contemplates diving into the pool.

Nuka does his pacing, to be sure, back and forth between the den entrance and the public window at the end of the enclosure. He also enjoys swimming his laps, jumping into the chilled pool and coming face to face with the visitors in the underwater viewing area. 

Entertaining the visitors.

Sometimes he plays with the visitors through the glass, especially the kids. Nuka is a people person.

Blowing bubbles, always a big hit

Nuka and his cousin Lee (in the Columbus Zoo) are the only male bears living in the US who have fathered cubs.  Nuka is the father of Astra and Laerke, girls born in the Detroit Zoo in 2020, and Kallik and Kallu, boys born in the Toledo Zoo in 2022. The mother of the Detroit twins is Suka, and her mother Crystal is mother of the Toledo twins. 

Up close and personal with Nuka

Nuka's twin brother Koda remains in Memphis alone. It is a mystery to me why he is not in a breeding situation, but there he is, alone.

Nuka up close.

Nuka and his twin brother Koda were born November 25, 2004, in Denver, to Voda and Kavek, who are also parents of Cranbeary of the Alaska Zoo, born three years earlier.

Nuka through the door of the den in Toledo.

Nuka and his twin brother Koda moved to Pittsburgh when they were two years old, and then in 2011 Nuka moved to Detroit alone, leaving Koda in Pittsburgh. In Detroit, Nuka lived with Talini for a time, and then Suka.

Suka and daughter Astra in 2021 Detroit.

Suka and Nuka's other daughter Laerke in 2021, Detroit. Laerke had health difficulties shortly after birth and was raised by keepers. She had a rescued grizzly bear companion Jebbie to play with. 

When Suka had her twins, Nuka moved to Toledo, where he fathered Kallik and Kallu, then back to Detroit.

Crystal in 2023, nursing the cubs in the den where visitors could watch. 

Underwater portrait of Nuka in Toledo.

When Crystal's new mate wildborn Kali did not work out, the two male bears were switched, and Nuka came back to Toledo, where he is today. They knew that Crystal liked Nuka, and she wasn't fond of Kali at all. Crystal is almost 28 years old, and has had nine cubs. She deserves a comfortable retirement, but the Species Survival program still has hopes that they can breed her. 

Nuka walking the boundary in Detroit in 2021,
with Suka and young Astra watching Dad.

Nuka also has a lot of fans in Detroit, where he lived for many years, and fathered twin girls Astra and Laerke with Crystal's daughter Suka. 

Nuka always has a friendly smile.

When Suka was busy raising Astra, and leaving Laerke to the care of the keepers, Nuka made the move to Toledo where he spent time with Suka's mother Crystal. The result was twin boys Kallik and Kallu, born in 2022.  

Kallik and Kallu at age 2 in Toledo

Nuka in Toledo

Nuka in Toledo. He will be 22 this fall.

Crystal (center) and her cubs Kallik and Kallu,
 fathered by Nuka in Toledo. 

Crystal at the cubs' birthday party. Crystal is in the middle.

Nuka went through a bad time when his reputation suffered after the death of Anana, who had moved to Detroit from Cincinnati. At first it was reported that Nuka, gentle Nuka, had killed her in a breeding attempt. It was later found, but not widely reported, that Anana had suffered heart failure, nothing to do with Nuka. Any wounds she had on her head resulted from Nuka trying to wake her up. 

Nuka's cubs are now mostly grown and in other zoos. 

Astra is in Como Zoo in St. Paul Minnesota. Laerke is in Point Defiance Zoo in Tacoma Washington. Kallik is in the Oregon Zoo in Portland, and Kallu is in the St. Louis Zoo in Missouri. 

A little family history:

Who is Nuka related to?

A bear named Clark was the great grandfather of Nuka and Koda, and also Cranbeary. 

 Voda, mother of Cranbeary, and twins Nuka and Koda, was daughter of Commodore who was born in Brookfield Zoo in 1972, the son of Clark.  This Clark was also the father of  the famous mother Arki, born in 1984 in the Brookfield Zoo and ending her days at the Louisville Zoo, and also of  Skeena, born in the Louisville Zoo in 1974. 

Arki became the mother of Marty, who was the father of all of Crystal's cubs in Toledo except for the last set of twins. So Marty and Nuka are related. Grandfather of Marty is Clark, who is great grandfather of Nuka. 

Skeena of Louisville was the mother of  twins Neil and Buzz, born in Louisville in 1995, and Neil is now in the Como Zoo;  Icee, who fathered twins Berlin and Yukon in the Cincinnati Zoo in 1989; Ulu born in Louisville in 1985 and the mother of Berit, longtime Cincinnati Zoo resident now living in Henry Vilas Zoo; and triplets Aquila, Aurora, Arcturus born in the Louisville Zoo in 1992. Of these bears, only Yukon has offspring going forward. He was the father of Aurora's four cubs: Lee of Columbus, Haley of Detroit, Anana of North Carolina, and Anoki of Rochester Of these four, only Lee of Columbus has offspring: Kulu now in Como Zoo. 

Astra arrives

 

Astra at Como Zoo

Visitors to Como Zoo in St. Paul Minnesota can now see four polar bears cavorting, swimming, wrestling, wandering and sleeping, with the arrival of young Astra, who just came from the Point Defiance Zoo in Tacoma Washington.

Astra makes herself at home at Como in the big pool. 

Kulu, on my most recent visit in July.

Five year old female Astra is being paired with six year old male Kulu, so there is quite a bit of playing and splashing going on.

I sent my St. Paul daughter Corinna to take some photos at the Como Zoo and tell me about how things are going between Astra and Kulu. Most of these are her photos.

Kulu and Astra get acquainted

 Kulu and Astra have the right hand side of the habitat, which has the deeper pool, and the older pair Nan and Neil have the other side with the big meadow and shallower pool. The keepers will slowly introduce Astra to the older bears.

Old folks Nan and Neil on the left hand side enclosure.

Kulu and Astra are enjoying getting to know each other, poolside.

                                             Yes, Kulu really likes Astra.

The keepers say that Kulu and Astra get along well, which bodes well for future cubs from the pair. 

Astra gathering her stuff

All mine!

Astra has a lot of fun with this simple plastic bottle.

Astra with her water toys. She loves that bottle, but they also have a giant pickle. And she also enjoys the baby pools as toys.

 

Astra likes to throw toys into the water, and play with them all at once.

Twin sisters in 2021 in the Detroit Zoo,
Astra in back, Laerke close. There is a ditch between them

Astra was born as a twin in the Detroit Zoo but grew up as a single cub because her sister was failing shortly after birth and had to have special care by the keepers. Their parents are Suka, daughter of Crystal and the late Marty, and Nuka. After several years of seeing each other across a divide, the twins, Astra and Laerke, were finally reunited. 

They were sent together to the Point Defiance Zoo in the spring of 2023, where the girls had a lot of fun playing together and making up for lost time. Laerke is quite a bit smaller than her sister, probably because of medication used to save her life when she was a young cub. She won't mind being alone, since she is quite people oriented, as a hand raised cub. She did have a young grizzly bear cub companion, Jebbie, for quite awhile in the Detroit Zoo, until he grew t00 strong for her. 

Jebbie and Laerke in Detroit

Laerke was happy when her twin sister joined her in Detroit, giving their parents Nuka and Suka the other side of the habitat. The twosome made the move to Tacoma where they lived for a year and a half.

Then last month, Astra was moved to the Como Zoo, while Laerke stayed in Tacoma, at least for now.

On one of the days my daughter visited, Kulu mostly stayed
on shore while Astra ran all about, and swam in the pool. 

 

Kulu yawns.

Here Kulu retrieves a fish. 

A nice fish snack for Kulu

Miss Astra comes along and wants some fish, and
 Kulu lets her have his fish. He is a real gentleman. 

Kulu is the son of Aurora and Lee of the Columbus Zoo. He was born as a single cub on November 28, 2019. His grandparents on his mother's side are Crystal of the Toledo Zoo and the late Marty. His father Lee is the son of Yukon and a different Aurora, who was born in Rochester NY. Kulu's grandfather Yukon was born in the Cincinnati Zoo. 

Kulu's mother Aurora and Astra's mother Suka are sisters, so they are first cousins. But with the small number of polar bears in the US, there is little other choice. Almost all the younger bears are from the same family.

You can tell Astra from Kulu in that Kulu is much larger
 and has shorter fur. Astra is little and is quite fluffy. 

I hope to visit the four bears at Como soon. It's great to see the different generations sharing and interacting.