Multiple fathers for reintroduced endangered Orinoco crocodile egg clutches

The Orinoco crocodile, Crocodylus intermedius, is one of the most threatened crocodile species in the world. There are now just a few wild populations remaining in Venezuela and Colombia. Excessive hunting until the 1960s and egg collecting for their local consumption decimated their numbers, and now new conservation efforts are aiming to revive their dwindling population numbers.

One such effort involved the reintroduction of one population by an international team of researchers led by Natalia Rossi Lafferriere from Columbia University, and can be found at the La Ramera lagoon at the El Frío Biological Station, Venezuela. I can’t imagine a better job than rearing endangered crocodile eggs for the purpose of reintroducing them into the wild when they were ready!

But how do you work out if reintroducing endangered species like this is a successful venture or not?

To test this, the team sampled 20 egg clutches (335 hatchling micro-crocodiles) for incubation in their laboratories, and were able to conduct genetic analysis on them in order to test to see who their fathers were. This is important as you can get a measure of genetic diversity within populations, which is a vital factor in whether or not populations have the capacity to survive. It’s probably also important to do this via genomic analysis rather than observation for what I’d think were obvious reasons.

What did they find?

Perhaps unexpectedly for humans, but quite expected for wild animals, the research team discovered that half of the egg clutches were actually fathered by more than one male! Of the 14 fathers inferred from genetic analysis, they found that only 6 contributed to a whipping 90% of the total offspring. Even more bizarrely, 3 of these 6 males fathered more than 70% of the total number of offspring. Full points for productivity to those chaps!

The evolution of females mating with multiple mating is known as polyandry, and can be achieved either through mating with multiple individuals during the same reproductive season, or actually storing sperm in the reproductive tract for later fertilisation.

This activity has rarely been observed in captive population of crocodiles, but has been documented in the wild for American alligators and the spectacled caiman, suggesting that multiple mating systems might be widespread in crocodilians and an important factor in their survival. These beasties and their ancestors have been around since a time around the origin of dinosaurs, after all!

These new results reveal the first evidence for multiple paternity in a reintroduced Orinoco crocodile population, and therefore supports the success of reintroduction efforts for this species.

Why is this important?

More than half of the living species of crocodilian are endangered, thanks to threats to habitat change, human disruption, and ongoing environmental changes. By gaining an insight into their reproductive behaviour, we can learn more about how to reintroduce these animals into the wild into sustainable populations.

In this case, multiple paternity might be important part of mating systems for increasing the overall genetic diversity in populations, as well as the total size of populations. These factors are often critical in maintaining flexibility and diversity in populations, and they play an important role in survivability at a population level, something that is becoming increasingly crucial for these endangered animals.

Other benefits of this can include sharing resources with mothers to ensure greater offspring survival, and greater selection of ‘higher quality’ mates, which is important for that well known concept of survival of the fittest. Darwin would be proud!

Successful reproduction is a vital and necessary first step in the recovery of the Orinoco crocodile. This is an excellent example of a successful reintroduction effort of a critically endangered species, and hopefully a sign that we can reverse the effects that led to their endangerment before it’s too late.

Continued conservation action will be important to mitigate ongoing threats to the Orinoco crocodile. This includes banning poaching, protecting their habitats, and will require a combined effort from governmental conservation authorities in order to create sustainable initiatives.

All is well that ends well too, and all crocodiles were released back into the wild as juveniles. Life, er, finds a way!

Earliest example of animal nest sharing revealed by scientists

An international team of scientists, including researchers from the University of Southampton, has shown that fossilised eggshells unearthed in western Romania represent the earliest known nest site shared by multiple animals.

The shells -- some complete and others broken into thousands of pieces -- are densely packed and encased in mudstone which formed part of the remains of a bird breeding colony, probably comprising hundreds of seperate nests.

Now in the collections of the Transylvanian Museum Society in Cluj Napoca, Romania, the samples date from the late-Cretaceous period (approx. 70 million years ago) and were discovered near the city of Sebeş in Transylvania by local palaeontologist Mátyás Vremir about nine years ago.

Led by Centro Regional Universitario Bariloche in Argentina, the scientists examined sophisticated electron microscope images of the unique, fossilised material from the site. They established it contains four different types of egg shell, indicating that four types of animals all shared the same nesting site; extinct birds within a group known as enantiornithes, birds of undetermined classification, gecko-like lizards and smaller predecessors of today's crocodiles.

Christian Laurent, Tizard Scholar and member of the Aerodynamics and Flight Mechanics Group at the University of Southampton, comments: "We know very little about the parental behaviour of Mesozic birds, We know they had nests, laid eggs and hatched young which were relatively mature and able to move around after hatching -- but evidence is scant beyond this. This research suggests they were tolerant of creating their nests, not only alongside other birds, but also reptiles."

The team, which also includes researchers from the University of Jinan (China), the Transylvanian Museum Society (Romania), the Royal British Columbia Museum (Canada), the University of Debrecen (Hungary), and Pavol Jozef Safarik University (Slovak Republic), has published its findings in the journal Nature Scientific Reports.

Their paper speculates that an area of plain created by seasonal flooding offered the enantiornithes safety from predators. It's also believed that their nest environments afforded shelter to smaller reptiles which benefitted from the security of the birds guarding their own nests. The researchers suggest that the lizard and crocodile type animals were not perceived as a threat to the bird eggs and nestlings -- possibly because they were much smaller than the adult birds and so not a predatory threat to them or their hatchlings. To date, this is the oldest example of this kind of ecological strategy.

Christian Laurent adds: "Evidence supporting our theory can still be seen today in Argentina, where lizards (Salvator merianae) co-habit and lay eggs inside the nests of the caiman crocodile -- safe in the knowledge that the female doesn't feed during the incubation of her eggs and poses no threat to the hatchling lizards."

Gatorama hosts CrocFest to help save species

Gatorama will host the International CrocFest this Saturday, Dec. 8, for the first time, and three “superstars of crocodilian conservation” will attend the semiannual fundraising event. It's also the first time the three will appear together to discuss the state of conservation efforts for the species.

The event, which had its start in 2010 as “Barbecue for the Crocs” at Crocodile Creek Bio-Center in Bushnell, is a fundraiser conducted by the CrocFest organization to benefit specific endangered crocodile species and individual researchers working on programs to conserve them.

The 2018 Winter CrocFest's beneficiary species is the gharial, a critically endangered, fish-eating and very territorial member of the crocodile family on the Indian subcontinent (Gavialis gangeticus is its scientific name), which is losing population. All proceeds will benefit the Gharial Ecology Project, the Gharial Conservation Alliance and many scientists in India who are studying the complex social structure exhibited by this subspecies. Adult male gharial, which can weigh up to 550 pounds, breed all adult females in their domain, which then nest communally.

CrocFest draws people from all over the world — crocodile keepers, private collectors, zoo board members, researchers, biologists, champions of conservation and people who love crocodilians (which include animals other than crocodiles, such as caimans). The event will be capped off by a lively auction of unique art, artifacts, collector items, zoological supplies and small reptiles. A dinner is served and an open bar is included along with the fun of “Gatorventures” at Gatorama.

The “trifecta of the crocodile world,” as Gatorama owner Patty Register described them, consists of prominent Australian educator and conservationist Grahame Webb, chairman of the Species Survival Commission for the International Union for Conservation of Nature; Rom Whitaker, an American Indian herpetologist and conservationist who founded the Madras Crocodile Bank Trust; and Jeffrey Lang, biology professor emeritus at the University of North Dakota and senior scientific adviser to the Gharial Ecology Project.

Mrs. Register, who operates the attraction on U.S. 27 with husband Allen, a state-licensed alligator trapper and farmer, said Gatorama actually will be closed for the day Saturday for the fundraiser but that anyone is welcome to join in the event.

“It promises to be the best CrocFest yet, and hopefully will raise more money than we have ever raised for crocodile conservation,” she said. The trio will give presentations about their work, and there will be a lot of social interaction and networking among the educators, experts and others expected to attend.

The park will be open from noon until 8 p.m., and the donation to crocodile conservation covers everything. “We'll be operating just like another day,” Mrs. Register said. “All the (usual) activities are available, but that $25 is a donation directly to CrocFest that covers admission, dinner and an open bar. And then there's an auction, which has all kinds of different items. It's turning out to be a real artsy one.”

It's like losing a part of your heart

Crocodile Hunter Steve Irwin passed away when he was attacked by a stingray while filming “Ocean's Deadliest” in 2006 at age 44, leaving behind two children. His daughter Bindi, who was just 8 years old at the time, admitted she is still coping with the tragic loss.

“I remember people coming up to me and saying, ‘I'm sorry for your loss, sweetheart. Time heals all wounds.' But that's just not true,” the 20-year-old recently told People magazine, which hit newsstands Wednesday.

“It's like losing a part of your heart, and when you've lost that, you never get it back,” she shared.

Irwin, who achieved international stardom for his televised death-defying stunts involving crocodiles, was at the Great Barrier Reef off Australia's northeast coast where his documentary was taking place at the time of his death.

According to witnesses on his boat Croc One, as well as one nearby diving vessel, a stingray's barb pierced Irwin's chest and lodged in his heart after he came close to it.

The family is determined to keep the legacy of their beloved patriarch alive.

Bindi, her younger brother Robert, 15, and their mother Terri, 54, have worked together to spread the message of their conservation nonprofit Wildlife Warriors throughout the world. They also launched a series on Animal Planet titled “Crickey! It's the Irwins,” which follows their lives as they work at the Australia Zoo.

“I'm sure hope dad would be proud,” said Bindi. “We really do try every day to make him proud and follow in his footsteps. I hope that somewhere he's out there going, ‘Yes! You did good!'”

Robert, who was just 2 years old when he lost his father, said he and his sibling have zero regrets in continuing Irwin's environmental mission.

“No matter where we go, or what we do, we'll always come back here,” said Robert. “This is our passion. It's a part of us and Australia Zoo will always be home.”

Palawan police recover body of fisherman attacked by crocodile

Authorities recovered Wednesday, November 28, the mutilated body of a fishermen who was believed to have been attacked by a crocodile in Balabac, an island town in the southernmost part of Palawan.

Police identified the body as that of 33-year-old Cornelio Bonete, a resident of Barangay Poblacion 5 whom relatives reported missing since Tuesday, November 27.

Senior Inspector Francis Rey Manito, Balabac police chief, told Rappler over the phone that the mutilated body of Bonete was found 4 p.m. Wednesday in Sitio Bual, Barangay Malaking Ilog.

Manito said Bonete's right arm and left foot were both severed from his body, while the right foot was broken. There were also multiple wounds all over Bonete's body, said Manito, most probably caused by crocodile bites.

Police authorities, along with Balabac mayor Al-hazni Astami, retrieved the body, Manito added.

Bonete, a resident of Barangay Poblacion 5, was last seen early Tuesday, November 27. His family said he did not return home since after he attended to his fishing boat.

Earlier, a local radio station broadcast an unverified report that the mutilated body of Bonete was found in Barangay Salang, some 6 kilometers from where he was last seen.

Balabac is known for recurrent human-crocodile conflicts, being the stronghold of saltwater crocodiles in the Philippines. Last month, a 16-year-old high school student survived a crocodile attack also in Barangay Poblacion 5.

Crocodile expert Rainier Manalo reminded Balabac residents to be wary as November starts the crocodiles' breeding or mating season. He said it lasts until February, while their egg-laying season falls in March until August.

“During this time crocodiles are very active and highly protective in their territories,” Manalo, executive director of Davao-based non-profit Crocodylus Porosus Philippines Inc, told Rappler in a text message.

Manalo's group has been continuously studying years of human-crocodile conflict in Balabac. They attribute the crocodile attacks to the increase in habitat loss due to mangrove conversion and debarking in major areas in town.

“Human-crocodile conflict is not easily prevented if there's an increasing habitat destruction,” he said.

The Palawan Council for Sustainable Development (PCSD), an environment agency tasked to implement R.A. 9147 or the Wildlife Resources Conservation and Protection Act, said its communication team held a crocodile awareness campaign in town recently.

“The only way to avoid [the human-crocodile conflict] is mitigation. Meaning, people should always be aware that crocodiles are present in their area and take responsibility, being diligent enough to avoid an encounter with crocodiles,” PCSD spokesman Jovic Fabello told Rappler in a separate interview.

Fabello added the presence of crocodiles in town is a “common knowledge to the residents and it saddens us an incident like this still happened.”

The Balabac municipal government previously told Rappler that its staff had also conducted information drives in affected barangays of Catagupan, Rabor, Poblacion and Agutayan, and also installed warning signs reminding vulnerable residents to stay away from river swamps identified as crocodiles' habitat.

Hippos Save a Wildebeest From Crocodile's Jaws

Watering holes are often exciting places to watch animals interact, and new video from Kruger National Park in South Africa doesn't disappoint.

While touring the massive park, a couple happened upon a wildebeest that had just been bitten by a crocodile. It's likely the herbivore had approached the water for a drink when it was ambushed from below. The wildebeest struggled to free itself but the crocodile kept a firm grip on the slender leg in its powerful jaws.

For nearly eight minutes, the wildebeest and crocodile were engaged in a ferocious game of tug-of-war, and eventually the wildebeest appeared to tire.

Slowly the crocodile began to drag the wildebeest under water. Crocodiles, with their long, heavy bodies and stubby legs, have the biggest advantage over large prey like wildebeest when submerged.

As the wildebeest becomes more and more overwhelmed by the water and the crocodile's persistent pull, two hippopotamuses approach from offscreen. Suddenly, they charge toward the crocodile, causing it to lose its grip on the wildebeest. The mammal broke free. But with a likely broken leg, it may not survive long.

So did the hippos rush in to "save" a wildebeest in need?

Not likely, says Douglas McCauley, a National Geographic explorer and professor at the University of California Santa Barbara. Despite the fact that they're herbivores too, hippos can be extremely aggressive. Earlier this month, a sleeping hippo in Kenya was startled by a lion and snapped the big cat's neck.

McCauley offered two theories for why the hippos, likely sub-dominant males, incidentally "freed" the wildebeest.

The first is that the crocodile had encroached too closely on the hippos' territory. Hippos and crocodiles, which both frequent watering holes, generally are wary of each other. Hippos are too big and powerful for crocodiles to eat and hippos generally confine their prey to vegetation. But when a crocodile gets within about two meters (six feet) of a hippo, the territorial mammals may snap or charge, says McCauley.

McCauley's second hypothesis, the one he says is more likely in this case, is that the wildebeest's splashing prompted the hippos to stake their territory.

"My best guess is that the hippos are acting very aggressive toward anything that tries to enter the water. They'll come charging in and try to drive you away," he explained. (Watch what happens when a hippo attacks a boat.)

In other words, while the hippos appear to be "rescuing" the wildebeest in the video, it's more likely they were aggressively claiming their territory.

So even though the video doesn't necessarily show a case of hippo altruism, McCauley says it's a great example of how animals co-habituate and share space in the wild.