Totoaba fish: Characteristics, habitat, threats and more….

The totoaba or totuava (Totoaba macdonaldi) is a species of marine fish, a very large member of the drum family Sciaenidae that is endemic to the Gulf of California in Mexico.  Join us to learn about one of the most coveted fishes on the market.

At present, this fish is in danger of extinction since its fishing and commercialization without control have put it in a critical state, drastically reducing its populations.

The government of Mexican President Enrique Peña Nieto, has implemented a program since 2015 for the rescue and conservation of totoaba fish in addition to the marine vaquita, both species closely linked to each other by applying a definitive closure in the Reserve of the Upper Gulf of California.

Taxonomy

Animalia Kingdom  Phylum: Chordata  Class: Actinopterygii  Superorder: Acanthopterygii

Order: Perciformes  Suborder: Percoidei  Family: Sciaenidae  Genus: Totoaba

Species: T. macdonaldi

 

 

The Totoaba Fish’ Main Characteristics

It’s a fairly large fish reaching adult males to measure up to 2 meters in length and weigh up to 100 kilograms. His eyes are small in relation to the rest of the body, which allows inferring that his field of vision is quite weak and limited.

Its jaw lacks protruding canines, the teeth of the pre maxillae are located in two rows in front to join laterally and form a narrow band.

 

In the inner row there is another formation of smaller teeth, while the outer ones are stronger and larger. In the same way his lower jaw is projected forming an Angle at the base, although his mouth isn’t prominent or oblique.

The dorsal and anal fins lack scales at the top but have a thin scaly sheath that covers the base of them. Moreover, he scales have a ctenoid shape, being large and thick.

The radii of these fins in the youngest specimens are very long and in the adult specimens the fin is truncated, leaving only the medium radii protruding.

The color of the body is golden and in some cases the back is a slightly blue tone, but as soon as the fish dies its body becomes silvery gray on the sides and in the belly.

While they are young, their body has dark spots on the lateral-back region  .

It’s estimated that this animal has a long longevity reaching up to 20 years, which makes it vulnerable to climatic changes or overfishing, since its sexual maturation and therefore reproduction can take 5 years, although in some cases even more arriving to take up to 6 and 7 years. We invite you to read our article the anatomy of fish to learn about such an interesting topic

Let’s meet it

How Do Totoaba Fish Reproduce?

Unlike other saltwater fish such as guppy fish, this species doesn’t show a sexual dimorphism that makes it possible to differentiate at a glance if a specimen is female or male, although at the time of reproduction it’s possible to distinguish the Female thanks to her bulging belly.

It’s also presumed that the female is larger than the male, although this information has never been corroborated.

In addition to this point, this creature  takes up to 5 years to reach sexual maturity, although it’s not known for sure what is the appropriate length and weight in which a totoaba fish is ready to reproduce.

In 1969, the General Directorate of Fisheries and Related Industries presented studies that show that the smallest sexually mature specimens measured around 1.21 meters in adulthood and weighed around 14,500 kilograms, which translated into a life of around 4 to 5 years to reach this size.

It’s presumed that males can begin to reproduce when they reach 4 years of age but females take a little longer.

On the data that is known is that the fertilization is external, that is, the female carries inside her body the eggs that must be fertilized by the male and puts them in a safe place, then the male releases the sperm on the eggs so that fertilization is carried out.

After this process, the totoaba fish doesn’t tend to take care of its offspring since it returnes to the south waiting for its eggs to hatch and develop successfully, as in the case of the surgeon fish.

Spawning.

This species of fish has a migration pattern called ontogenic, which means that when they reach adulthood they migrate to the Colorado River Delta in the Upper Gulf of California during the winter and spring seasons, approximately at the end of the month of February and beginning of March, extending until the beginning of June.

For this egg laying process, females mainly use the mouth of the Colorado River.

But despite knowing this information, there are no data that  indicates the day or time in which the female spawns, nor are there studies that describe the appearance, structure, color or size of eggs.

Of what there is data is that the ovules that have been taken from the ovary, when they are preserved in formalin for a period of 5 hours tend to have a yellow but somewhat transparent color.

On the other hand, when the ovaries were observed using a microscope, they were found to contain many eggs in various degrees of development that had a diameter ranging from 0.1 to 0.8 millimeters.

In addition to this they had a single oily drop without observing any other characteristic that allows identifying the eggs when they are in the plankton after posts.

Offspring

The young specimens remain in the waters near the coasts until they are between 2 and 3 years old, which makes them freshwater fish until the moment of their first migration to the sea, when they head south on the mainland but they return every year to the same place they were born to put their young too, a case very similar to salmon.

It’s estimated that in these first two years of life, the totoaba fish will grow 17% of what will grow during its entire existence. During the first years, the growth will be accelerated but at 5 or 6 years of life the growth of the fish decreases or even stagnates.

Let’s keep learning about them

What does the Totoaba Fish Feed On?

This is an omnivorous fish, which bases its diet mainly on smaller fish and shrimp, in addition to the intake of algae and plants they find in their way.

However, the contamination of the beaches means that there is less food for this species, which contributes to its disappearance.

Young specimens tend to eat amphipods, and benthic crustaceans, as well as young grumpy fish.Adult specimens may also follow the same feeding pattern, although they prefer larger prey located on the surface, in the pelagic area such as sardines, anchovies and crabs.

There is not much data about the totoaba fishes’ feeding habits since the change in water pressure when it’s taken out of the sea causes the animal to regurgitate its food.

They have a special predilection for anchovies, so they usually swim in waters a little deeper than the schools of such species to follow them and be able to catch them.

Due to this behavior the fishers of the totoaba fish closely follow the anchovy formations in order to catch them. When using hooks, people use as bait, in addition to anchovies, smooth, saws and sea bass.

Distribution and Natural Habitat

The totoaba fish is a tropical fish that lives in somewhat warm temperature locations. It prefers to make up his home in the depths of the ocean although in many occasions he goes up to the most superficial areas.

It originates almost exclusively from the Pacific Ocean more specifically from the northern Gulf of California or Mar de Cortes, covering the countries of the United States and Mexico.

In addition, another family of this same fish is found in Lake Maracaibo in Venezuela.

At the beginning of the twentieth century, the totoaba fish could be found starting from the mouth of the Colorado River to reach Concepcion Bay in the West of the Gulf and also to the mouth of the River fort in the East.

But today, according to reports of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in 2010, it’s believed that it can only be found in the Upper Gulf of California.

An exciting fact could be seen in the first release of the totoaba fish carried out by the Autonomous University of Baja California through the Faculty of Marine Sciences in 2016. This demonstrates the enormous effort that environmental groups are exerting to manage to recover the population of said fish.

Let’s enjoy this wonderful sea…

The Totoaba Fish Endangered.

The main cause of the extinction of the totoaba fish is due to the strong demand of the Chinese country of the animal’s swim bladder since the 1920s, when this organ used to be valued at US $ 5, but the remaining 100 kilograms of the animal were only valued at 2 US $.

totoaba fish: the totoaba swim bladder sales in China

As a result, the population of this species has reduced around 95% since 1942 when its market had a rise.

During these years, up to 2,270 tons of specimens were taken per year, while by 1975 only 59 tons could be taken out.

Another important point to consider is the damage caused by shrimp fishing, since totoaba fish get usually trapped in the traps when trying to feed.

Degradation of the Spawning Area.

The different dam projects carried out by the US government, such as the Hoover dam completed in 1935 and the Glen Canyon dam completed in 1963, are considered to have significantly reduced the water flow of the Colorado River. 

Such a  fact has caused the juvenile specimens of totoaba fish to have a lower growth rate than the rate they had already established before construction.

It’s believed, although there is no strong evidence to prove it, that the construction of some dams along the Colorado River by the United States government has had an impact on the water flow of the river and therefore a negative effect in the growth rate of juveniles that grew at a faster rate before the works  were carried out.

But despite having this hypothesis, it seems questionable.

It’s logical to think that if a species is dependent on an estuary environment, that is, a space affected by the intense currents where the salt water of the sea and fresh from the river meet, the lack of this area or the cessation of the tide can make the species is extinguished.

However, considering that the construction of the dam was carried out at least 80 years ago but  the totoaba fish continue to use the same environment of the Upper Gulf of California for its reproduction, it’s inferred that the juveniles are able to adapt to the changes that the ecosystem has had due to the cessation of freshwater flow, since they can withstand a salinity level of between 11 and 40 ups.

It’s thought that totoaba fish and especially juveniles prefer the area of ​​the Upper Gulf of California for their habitat because of its substrate and water depth.

This is why the best way to preserve this species, is the simple preservation of the environment as such to make the animal return year after year to spawn.

Totoaba fish’ Marketing

As mentioned above, this species is very valued in European and Asian markets, especially in countries such as China, where it’s considered to have highly effective aphrodisiac and healing properties. Its fishing and commercialization had a great boom in the 1920s, due to the demand of this Asian market.

This fish began to be caught during its most vulnerable stage, which is in the maturation stage of juveniles in the Upper Gulf of California.

In addition, the fishermen captured the species during the migration months when it moves towards the mouth of the Colorado River to spawn which caused its population to suffer greatly since its renewal was not possible.

It’s marketed in the black market, where it has been considered an even more expensive product than cocaine, since a kilo of swim bladder of the totoaba fish is sold to Asian traffickers for a value between 468 to 1871.9 euros, who in turn sell it to consumers for a figure that can rise to 56,159.5 euros. This price is above the aforementioned drug that can cost between 30,000 or 35,000 euros per kilogram.

Other Facts

Its value varies from country, costing in Mexico about 8 thousand dollars, around 16 thousand dollars in the United States, while in China it’s much more expensive around 60 thousand dollars.

Its fame is because it’s believed that once the swim bladder of the totoaba fish is cooked in a soup, it can lower cholesterol, improve blood circulation, rejuvenate the skin, grant longevity, in addition to the aphrodisiac qualities that it confers.

Illegal Fishing of Totoaba fish.

Being a seriously endangered species, a network of traffickers who fish with nets has been implemented with everything they get in their way with the desire to find the totoaba fish. Not only do they harm the fish, also in their eagerness to achieve it, dolphins, sharks, turtles, rays, everything that gets entangled in the nets can die.

But the saddest thing of all is that many times they only remove the swimming bladder from the fish, an organ of great value, and then throw away the rest of the animal back to the sea flooding the beaches of dead fish.

Once the animal’s gaseous organ has been obtained, the traffickers manage to disguise their loot and be able to pass it to the outside of the country; for this they use suitcases, milk cans and even car wheels.

The boats used for this feat are mainly large, which during the time of greater abundance of the totoaba fish are dedicated to their capture, while in the months of less fishing alternate with the collection of shrimp.

Larger ships may have a collection capacity of between 16.4 to 68.3 tons. But there are many more small boats that are commonly called «pangas» that measure about 5 meters with a capacity between 2 and 4 tons.

The most affected species by the poaching of the totoaba fish in addition to the fish in question is the marine vaquita, an odontocete cetacean whose population was estimated at 97 specimens by 2015. And by 2016 the situation of the marine animal does not improved since its population decreased by approximately 40%.

Let’s keep learning about this pratice

Protective Measures for Totoaba Fish.

Justice seeks to stop the illegal fishing of totoaba fish in the waters of the Gulf of California. The Ministry of National Defense and the Federal Attorney for Environmental Protection, captured recently 6 individuals who tried to traffic the totoaba fish

Since 1975, the Mexican government has made a permanent ban official seeking to respond to the poaching and illegal hunting of totoaba fish.

In 1976, the fish became part of the list of endangered species carried out by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), in Appendix I.

The US National Marine Fisheries Service made the fish totoaba part of its own list of endangered animals under federal registration 44 (99): 29478-29480. Today this species is cataloged under the «critically endangered» modality on the IUCN red list.

Since 1993, a total and definitive prohibition on the hunting and fishing of totoaba fish was decreed, with which, despite everything, about 17 tons of the animal have been seized in recent years.

In addition to these decrees and status, there are two sustainable animal farms that seek to repopulate the sea with the totoaba fish. These farms are one at the Autonomous University of Baja California and the other is called Earth Ocean Farms in La Paz BCS.

In these farms the natural conditions that the Totoaba Fish must have in their natural environment are simulated so that the reproduction is carried out successfully.

As part of these measures the conditions of summer and extreme winter are represented to indicate to the fish a reference of when the year begins and ends to make possible two reproductive stages per year instead of one as do the specimens of fish totoaba in the wild .

To avoid stress, researchers take great care not to produce any loud sounds or vibrations that can affect fish cycles.

Let’s watch

 

 

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