Mobula Munkiana

It is that time of the year again! Every spring we have a very special gathering in our front yard: thousands of rays aggregate in a breathtaking spectacle. They are Munk´s pygmy devil ray or Mobula munkiana, locals know them as “tortillas”, because the sound they make when jumping out of the water, reminds the clapping of hands produced while making tortillas.

They are cartilaginous fish, related to sharks, and they inhabit the Eastern Pacific Ocean, from Mexico to Peru. They reach a maximum disc length of 4.2 ft (130 cm), with an average of 3 ft (100cm). They are filter feeders, and they follow the zooplankton blooms, moving around the Baja peninsula with them. This time of the year, they can be seen in our area, when the conditions are ideal for feeding and reproduction. All around the bay, they can be seen swimming gracefully in the water, hundreds of them together, moving their fins like birds flying, it is truly nature´s wonder. But they can also be seen out of the water: moving their wings and gaining enough momentum to propel themselves in acrobatic jumps, sometimes many of them at the same time. Nobody knows exactly why they jump, there are different theories, but I like thinking it is just pure joy.

For years they were fished till they were put in severe danger of extinction. They are very sensitive to overfishing because they have slow reproductive strategies, like many other cartilaginous fishes. They are aplacental viviparous and they only give birth to one pup, after a gestation period of 12 months, so it takes them a long time to recover after the removal of many individuals. Now they are protected, and we have seen increasing numbers, but they are still listed as vulnerable in the IUCN Red List. One of their main threats is bycatch from coastal fishing nets. Swimming with them is a great attraction for ecotourism, making them way more valuable alive than dead and favoring conservation efforts.

Common Dolphin

Common dolphins (Delphinus delphis) are the most common cetacean in the world, they are found worldwide, through tropical and temperate waters, nearshore and offshore. Despite their name, they are not the dolphin we have in mind as the “classic dolphin”, being this one the bottlenose dolphin, popular in media or aquariums. Common dolphins have a well-defined long beak, a black-grey back, and a dark patch around the eye, they can be easily recognized by a pale to tan hourglass or crisscross pattern on the sides of their bodies.

They form large groups for hunting and socializing, it is not rare to see hundreds of them in a group. Sometimes, they can form bigger groups called “super pods”, gathering thousands of individuals. They are very playful when they swim in groups and enjoy breaching and playing with waves, they are known for swimming along with boats, either racing at the front or playing at the wake that is formed behind.

Because of their wide distribution, they have a varied diet, feeding on schooling fish like anchovies and sardines, among other species, and enjoy eating squid too. They have been recorded to make dives up to 200 meters (660 ft) deep.

Recently we had big groups of common dolphins in the bay, and what is even better: there were many babies with them! Given that newborn calves measure 7 to 100cm (2.3 to 3.3 ft) I would say these babies were recently born, I had never seen such

Paper Nautilus or Argonaut

Today I want to introduce you to one of the most fascinating marine creatures. These beautiful and delicate shells you see, didn´t belong to a snail or a crab, they belonged to an octopus, a female octopus to be more precise.

Paper nautiluses or argonauts are a group of pelagic octopuses. Unlike their ground dwelling cousins, they spend their lives drifting in the water column, so they evolved in clever ways to adapt to this environment. Argonauts exhibit extreme sexual dimorphism in size, lifespan and features. Females can grow up to 30 cm (12 inches), with their shells while males rarely reach more than 2cm (0.8 inches). Males only mate once in their short lifetime, but females can reproduce many times during their lives. Females have been known since ancient times, because of a unique characteristic, while males were only described in the late 19th century.

The most particular feature of these animals belongs to females too: they have two special tentacles that secrete calcite. After mating, they start producing a delicate papery shell, lay their eggs inside it and get cozy themselves. They capture air at the surface and then seal it inside the shell, using it for buoyancy control, like a hot air balloon. They can control the size of the air bubble to keep their position in the water column. This way they travel, following the current accompanied by their eggs without expending energy.

A paper nautilus’ shell is a rare finding, if you are lucky to find one, treat it carefully, it’s a little and delicate treasure, a part of a creature with a unique life story!

Blue Whale

Just a few days ago we had an incredible encounter: while out on a boat, we found not one, but two blue whales in our bay. We were observing a humpback whale when suddenly, we heard a very loud blow close to our boat: there it was, a gigantic creature just at our doorstep. The sound of a blue whale´s breath is incredible, it is so loud it gets inside your chest, no doubt a powerful feeling to hear one close by.

Blue whales are the largest animal known to have ever existed. They can live up to 80 or 90 years and reach a maximum length of 30m (98 ft) and weigh up to 200 tons. Their heart is the size of a car! They perform long migrations, traveling from their summer feeding grounds in the polar regions to their winter breeding grounds in waters near the tropics.

Despite their size, much of their life story remains a mystery. They are generally solitary or gather in small groups, mothers with their calves being the most common aggregation. They migrate during winter and spring to the Gulf of California for feeding and breeding. In Loreto area, females with their newborn calves have been observed.

They are baleen whales, meaning they do not have teeth, but baleen plates that they use to filter their food. Their diet consists almost exclusively of krill. Their stomach can hold one ton of krill and they need to eat about 4 tons of krill each day.

Blue whales produce some of the loudest and lowest frequency vocalizations in the animal kingdom, and their inner ears appear well adapted for detecting low-frequency sounds. They emit a series of pulses, groans, and moans, and it’s thought that, in good conditions, blue whales can hear each other up to 1000 miles away. Scientists think they use these vocalizations not only to communicate but, along with their excellent hearing, to sonar-navigate the lightless ocean depths.

Like other whale species, they were abundant in nearly all the Earth´s oceans, until the 19th century, when they were hunted almost to extinction. The International Whaling Commission banned blue whale hunting in 1966, but they’ve managed only a minor recovery since then. Today they are listed as Endangered and face man-made threats such as ship strikes, pollution, ocean noise, and climate change.

Gray Whale

This time of the year we receive one of the most popular visitors of the Baja Peninsula: gray whales (Eschrichtius robustus). Every winter, gray whales embark on an epic trip from their summer home in Alaska´s waters to the warm waters of Baja California´s lagoons. This is one of the greatest migrations in the animal kingdom, a round-trip of around 20000 km (12000 miles), an epic journey full of dangers. This week I would like to share their story, because it is one of hope, one that shows us that if we act soon, there is still time for life to bounce back.

During the mid-1800s and early 1900s, gray whales were slaughtered for their meat and fat to almost extinction. In their nursing lagoons of Baja California, they were easy prey. Fishermen called them “devil fish” because when losing their calves to whalers, the mothers would destroy their boats. There was an open war between whales and humans, one that whales were losing.

Finally, gray whales became internationally protected in 1947. After almost disappearing, the population rebounded, going back to almost pre-whaling numbers.

The war was over and, after decades, the whales changed the way they saw humans: in San Ignacio, gray whales started approaching fishermen’s boats, not to attack them, but to greet them. The whales seemed to want people around and even allowed fishermen to pet them. Such a special interaction brought ecotourism to the fishing villages, which are visited every year by people from all over the world.

Today, gray whales and people are intimately connected, they are part of the local culture and are highly regarded, being one of the most iconic species in Baja California.

Whale Sharks

Whale shark (Rhincodon typus), 0% whale and 100% shark, whale sharks are the largest fish in the world, reaching up to 18m (60 ft). Primarily pelagic, they can be found in both coastal and oceanic habitats. They lack proper teeth having only tiny ones and filter pads in their gills. They are filter feeders, one of only three known filter-feeding shark species (along with the basking shark and the megamouth shark). They feed on plankton and other small animals like baitfish and squid. They swallow water either by opening their mouth and swimming forward or by active suction, opening and closing their mouth. The water is then expelled through the gills, which filter the food. A juvenile whale shark is estimated to eat 21 kg (46 pounds) of plankton per day.

Whale sharks are found in tropical areas around the world, including the warm waters of Mexico from the Sea of Cortez to the eastern Mexican coast in the Caribbean. They are generally solitary animals but sometimes gather in large groups to take advantage of good feeding opportunities.

They are gray or gray-blue with a beautiful pattern of white lines and dots. This pattern is unique to each individual, like a fingerprint, and can be used for identification. In La Paz area they gather from November to April to feed in the plankton-rich waters of the Bay. Despite their enormous size, we still don´t know much about these animals, and their growth, longevity, and reproduction are poorly understood. They are classified as Endangered on the IUCN Red List.

Long-spine Porcupinefish

This smiley face, pokemon-looking fish is one of the porcupinefishes species we can find in our area. Called sometimes pufferfish, they are related but belong to a different family than the proper puffers. Both families are morphologically similar, but porcupine fish have spines that cover their bodies.

They are found in temperate and tropical seas worldwide, usually close to shore. If you have ever been snorkeling or even just walking on the beach in La Ventana, I am pretty sure you have seen one! They have big round eyes on the sides of their rounded head, with a wide frontal mouth typically left open. Their teeth are fused together, creating a strong, beak-like mouth capable of cracking the shells of snails, sea urchins, and hermit crabs that make their diet.

If they feel threatened, they can inflate their bodies by swallowing water, ballooning up to three times their normal size. The spines that cover their bodies radiate then outwards, giving them another defense mechanism. They only recur to this “puffing” ploy when desperate, as they lose mobility when inflated, they normally rather just hide from predators swimming into a crevice. When approached by snorkelers and divers they usually move slowly away looking for a hideout.

Some porcupinefishes are poisonous, having a substance called tetrodotoxin in their internal organs. This deadly neurotoxin is 1200 times more toxic than cyanide. As a result of all these defense mechanisms, porcupine fish don´t have many predators, but adults can be preyed upon by sharks and orcas. Sea lions and dolphins sometimes have been seen playing with an unfortunate inflated porcupine fish, as if it were a beach ball.

In some places, they are eaten as a delicacy and the South Sea islanders once used the spiked skins of porcupinefishes as helmets.

Sea Lions

California sea lions (Zalophus californianus) are found on the West Coast of North America, ranging all the way from southeast Alaska to central Mexico. In Baja California, they can be found in multiple locations along the Sea of Cortez and in the Pacific Coast. These charismatic animals congregate in rocky spots where they form colonies, there are about 13 identified colonies in the Sea of Cortez. 

California sea lions are sexually dimorphic: adult males are larger than females and have a thicker neck, they are dark brown and have a pronounced bump on the forehead called sagittal crest. Adult females are golden brown or blonde and way smaller. Juveniles of both sexes are brown as well, so it can be difficult to distinguish their sex.

Feedingmainly offshore in coastal areas, they eat squid and different fish species including anchovies, mackerel, and sardines. They are very social animals, and they use numerous vocalizations to communicate. Getting close to their area, you are always welcomed by an endless barking sound: a sea lion colony can be a very noisy place! Females and pups communicate using vocalizations that are unique to the female and pup. A female can locate her pup among hundreds of others by her pup’s vocalization.

In Espiritu Santo Archipelago, close to La Paz, located in a UNESCO Heritage Area, resides one of the biggest and healthiest colonies in this area. This colony had scientists puzzled for some time: while other nearby colonies were decreasing due to the reduction in local fish stocks, this one was thriving and growing! A scientific investigation discovered that these sea lions had learned to dive deeper and feed on deeper water fish than other sea lions. This means that at some point they adapted their feeding habits and their skills when their usual prey started to be scarce. 

Sea lions are intelligent and very charismatic animals, and it’s a privilege to see them wild and free at our doorstep. They can be curious and very playful with humans, interacting with them can be great fun, they are surely the puppies of the sea.

Osprey

A pretty common sight when driving through Baja are the majestic ospreys, always looking out from their nests, usually on top of light poles or in poles especially placed for them. Ospreys are diurnal birds of prey, with a wide distribution: they are found in all continents but Antarctica. They are usually migratory birds, but not in Baja California, where our mild winter is comfortable enough for them to stay all year around.

Ospreys are found close to water bodies, such as estuaries, marshes, rivers, or by the seaside. Fish are their favorite prey, they actually eat barely anything else: fish make up to 99% of their diet! They hunt by diving to the water’s surface from some 30 to 100 feet first. Gripping pads on their feet help them grab fish from the water and carry them for great distances. They are very well adapted to the aquatic environment: an oily waterproof coating on their wings allows them to dive without sinking and they can close their nostrils when submerged in water.

Ospreys are usually monogamous and often mate for life. The male selects a suitable place and together with the female, they collect materials and build a large nest. The females lay 2 to 4 eggs and the pair incubates them. 

Watching ospreys fishing, protecting their nests, feeding their young, or just vigilant on top of a cardon is a great pleasure to enjoy all year round in Baja.

Manta Rays

Giant oceanic manta rays (Mobula birostris) are the largest species of rays in the world. Reaching a maximum disc width of 700cm (22ft) with an average of 400-500cm (13-16ft) and a weight of 2000kg (4400pounds), they are graceful and gentle giants.

They are cartilaginous fish, meaning their skeleton is made of cartilage instead of bone, they are related to sharks. Mantas are filter feeders: gliding gracefully through the water column with their mouth wide open, they gulp down large amounts of water, collecting with their gill plates the zooplankton and krill that make their diet.

With the largest brain-to-size ratio of any fish, they are highly intelligent animals. There have been studies showing that mantas may recognize themselves in the mirror, an ability that indicates a high cognitive function. 

A common sight in the past in La Paz and Cerralvo area, they suddenly disappeared for a while, the reason for their disappearance is unknown, though overfishing has been pointed out. In the past years locals and tourist have gladly witnessed their return to La Reina, close to Cerralvo island, with most sightings during the warm summer months.

Classified as endangered in the IUCN Red list, their main threat is overfishing, as bycatch or as a target for their meat, but specially for their gill plates, valuable in the Asian market for traditional medicine.

Seeing these animals effortlessly flying through the water like massive birds is surely magical and looking into a manta ray’s eyes is an unforgettable experience: their eyes are inquisitive and intelligent. Through that alien look we can connect to a different world: the wild and mysterious big blue.