This was known after the researchers carried out a stimulus through recordings of human babies and primate babies. The crocodiles are then attracted to the sound of whining. The more anxious the sound, the more interested the crocodiles became.
The test was carried out at the zoo in Agadir, Morocco, which has more than 300 Nile crocodiles ( Crocodylus niloticus ). They installed loudspeakers next to four pools containing 25 crocodiles each. The loudspeaker emits a series of cries from chimpanzees ( Pan troglodytes ), bonobos (paniscus ), and human babies.
Nicolas tests the intensity of the sound through various situations for moments of various emotions. Human babies, for example, are recorded at baths and vaccinations.
Male and female crocodiles respond to screams by looking for the source of the sound. However, their response depends on the characteristics of the cry they hear. Crocodiles were more likely to respond to recordings of the most anxious babies’ cries.
It is possible that these predators perceive danger as a cue to find potential food nearby. A helpless young mammal calling its mother sounds like lunch.
It could be that both male and female crocs were more likely to move towards the sound of the cries which might explain whether the animals were trying to harm or help.
Doody said crocodiles had evolved to recognize distressed cries because they were caring mothers – but they had the flexibility to use the same skills to hunt.
The phenomenon of crocodile sensitivity acting out of parental fears or appetite for prey is a unique new finding. Proving that there are animals that understand the language of communication from other animals.
Black Badas Crocodile, Protected Wildlife Icon of East Kutai
This species lives in the freshwater waters of the Menegara Wetlands in the Essential Ecosystem Area [KEE] of the Menegara – Suwi Wetlands [LBMS], East Kutai Regency [Kutim], East Kalimantan Province.
The crocodile is registered as an Appendix 1 animal, meaning that it cannot be traded according to CITES and is in a Critically Endangered conservation status based on the IUCN.
Through the Yasiwa – Ulin Foundation Consortium Program, the black badass crocodile, which has become one of the icons of the East Kutai Regency Government, is being preserved along with its habitat.
Unlike the estuarine crocodile, the black badass crocodile tends to be calmer and less aggressive when meeting humans.
A researcher of the Yasiwa Consortium – Ulin Foundation, Ngareng Mohammad Zulfikar, expressed this.
According to him, KEE LBMS provides enough food for the crocodile. Even though fishermen also look for fish in their habitat, the food is still abundant and does not decrease.
Ngareng explained, to ensure its existence and distribution, the consortium routinely conducts research and surveys. One of them is in the Menegara Wetland which is located between two rivers, the Kelinjau and Telen, joining at a downstream junction to the Kedang Kepala River. Furthermore, it flows into the Mahakam River.
Apart from Menegara, black badass crocodiles are also found in Lake Suwi and several lakes in Muara Ancalong District. Crocodiles will make nests and are easily recognized by fishermen. Not infrequently, puppies appear on the surface near the trees.
The black badass Crocodile population
The person in charge of the Consortium Project, Suimah, explained that the black badass crocodile population cannot be counted directly. But in Behler’s research [2010 – 2012], which was calculated on the cruising area.
Based on estimates, researchers found as many as 75 individuals in a survey area of 20 square km. If calculated from the area, the estimate for black badass crocodiles in the entire Mesang area is around 300 non-hatching individuals. That number could be more because it is influenced by migration due to the condition of the surrounding landscape.
For the survey process, the difficulty that is often experienced by consortium researchers is the lack of visibility of moonlight because it is covered by the forest canopy. Except for using lighting tools such as flashlights and lamps.
For information, black badass crocodiles are categorized into four size classes. There are hatchlings [< 30cm], juveniles [30-80 cm], under adults [80-180 cm], and adults [> 180 cm].
Crocodile Found in Oldest Ancient Sea
Paleontologists have discovered a new Thalattosuchia—an ancient “cousin” to modern crocodiles. This finding could make the creature the oldest of its kind ever found so far. Fossils found on the Jurassic Coast of England include parts of Turner’s head, spine, and limbs such as Hingley.
The recently discovered Turner Suchus Hingley fossil represents the only complete Thalattosuchia of its time. Derived from the Jurassic, early Pliensbachian period, which is about 185 million years ago. In a study published in the Journal of Vertebrate Paleontology, researchers say that this new fossil discovery helps show that Thalattosuchia and other crocodile-like animals originated about 15 million years further from Turner Suchus.
In fact, during the publication of the research paper, says Eric, a Thalattosuchia skull was found on the roof of a cave in Morocco (the pre-Plin Bachian period where Turner Suchus was found). This finding strengthens the researchers’ ideas about evolution and extinction.
Thalattosuchia has very large supratemporal windows. This is the area of the skull that houses the jaw muscles. This suggests that Turner Suchus and other Thalattosuchia have enlarged jaw muscles that allow for rapid bites. It is also possible, as in modern crocodiles, that the Turner such us the supratemporal region had a thermoregulatory function that helps it maintain body temperature.
Protected and respected, this Papuan endemic crocodile is still being hunted
This last crocodile is usually called the Irian crocodile or the New Guinea crocodile. Its existence on the large island of Papua, makes it have many names.
In a survey on the status and conservation action plan of Crocodylus novaeguineae conducted by Jack H. Cox and released by IUCN, it was stated that other names are New Guinea Crocodile, New Guinea Freshwater Crocodile, freshwater crocodile, black crocodile, freeware puk-puk, black pela puck, and wahine hula.
In his survey, Jack explained that the maximum documented adult size was around 3 meters for females and 3.5 meters for males. However, larger sizes and suitable skins are regularly reported in the Sepik River region of the country of Papua New Guinea.
The hunting of this crocodile species was also highlighted in Jack’s research. Even hunting started during the Second World War and reached its peak in the 1960s.
” Crocodylus novaeguineae prefers freshwater habitats, and is found in most of the freshwater river systems, swamps, and marshes of the vast New Guinea,” Jack wrote in his research.
According to him, from 1986 to 1992, a project funded by the FAO [Food and Agriculture Organization] conducted a basic survey and developed a system for collecting eggs and chicks for captive crocodiles. During the same period, there were initiatives and enforcement of regulations to deal with widespread illegal poaching and smuggling of crocodile skins.
“During the late 1994 to 1998 period, Indonesia imposed a moratorium on the export of all crocodile products, except for private ownership,” Jack wrote again.
In Papua, one of the tribes known to have a tradition of hunting crocodiles is the Bauzi Tribe in Membramo Raya. This tribe catches crocodiles to consume their meat and then sells their skins. In fact, crocodile skin is now of high economic value. There are two types of crocodiles that are hunted in Papua, namely the estuarine crocodile [ Crocodylus porosus ] and the Irian crocodile [ Crocodylus novaeguineae ].
Since 2018, the Regional Government of Papua has legalized the marketing of crocodile skin. This permit was issued because crocodile skin is considered a proud craft and is a regional asset. Even though it has been legalized by the local government, there is a standard for the age of a crocodile whose skin can be used, which is over one year old or has a stomach width of 12 inches.
Crocodile leather crafts can be categorized as exotic leather crafts and have high sales value in the international market. Crocodile skin that has been tanned can be processed into products in the form of wallets or belts.
Respected but still hunted
Hari Suroto, a senior researcher from the Papua Archeology Center, said that Irian crocodile hunting was also carried out at Lake Sentani and was usually carried out in groups during the day. These hunters initially burned the undergrowth that grew around the sago forest swamp, so that all the animals hiding there would enter the waterways.
The hunters then poisoned the waterways with tuba roots, so that all the animals would rise to the surface of the water, and then they speared them.
He described that on the back of the Irian Crocodile, there is a dark transverse line. The tail is black-brindled and broadly striped. This crocodile roams at night, if there is a beam of light that hits the right eye, it is as if the eye emits a red light.
According to him, this fishing method is very risky to damage the environment, and not infrequently when they burn bushes, nearby sago palms also catch fire. In addition, by poisoning the waterways, small fish also die.
Hari explained the existence of this species in Lake Sentani is starting to be difficult to find. Hiding in parts of the lake far from settlements, or away from human activity.
“Apart from that, their habitat has also been damaged due to the conversion of sago forest land to housing or the widening of the main road to Sentani Airport,” said Hari, in mid-May 2021.
Hari explained that in the past culture, the Sentani community used the skull of an Irian crocodile as a home decoration. In addition, crocodile motifs are also carved on the boats and poles of their traditional houses. However, it is not arbitrary that people can use crocodile motifs on their boats or traditional house poles.
The crocodile motif is a symbol of the ancestral totem of Ondoafi [Tribe Chief] Dondai, in the western part of Lake Sentani. Totem itself is an object or animal that is considered sacred and revered.
Dondai Village, Waibu District, Jayapura Regency is part of the Yope site. Yope in the Sentani language means village on the bay. Yope is a bay part of the western part of Lake Sentani. The Yope site is believed by the people of Kampung Dondai to have been used as a settlement by their ancestors.
This is evidenced by the findings of pottery with crocodile motifs and net pendants made of fired clay. In the past, Yope was a fishing community with houses on stilts above the surface of the lake.