Many fish stock species could not be established due to the sensitivity some fish species had to the sea water not being an exact replica of Earth sea water (sometimes lacking the right microflora, or present with the wrong ones), but there is still food in the oceans in the form of seaweeds, krill, California mussels (Mytilus californianus), new descendant species of the Common Prawn (Palaemon serratus), Humboldt Squid (Dosidicus gigas) and just two species of fish.

Humboldt squid and the common prawn are the most common macroscopic visitors to the West Catland coastline, while mussels live here on the rocks. New species descended from the Peruvian Anchoveta (Engraulis ringens) are only found on the Southern half of the coastline, and descendants of Steelhead trout (Oncorhynchus mykiss irideus) an even smaller section of the South coastline. The original species are still extant but not in these warmer waters. Adult humboldt squid are the top predators of this habitat while in the water, and fully grown adults have incentive to visit the shallows in search of pey animals entering the water from the land.

Beach Cats (Catus rugosus) of the West coastline had evolved a strategy against the heat of using water sources to stay cool. As a result these cats have a higher encounter rate of water prey, and have some minor adaptations to a lifestyle of daytime swimming and aquatic hunting such as webbed toes and shortened fur. They also have a peculiar wrinkled appearance visible due to the extremely short, velvety fur. This is another strategy against the heat, as the wrinkles both cast shadows (lowering total surface sun exposure) and give the cat an overall higher surface area to radiate heat from. At the most extreme of it's range North towards the equator the cat's ears are also shorter due to being the worst burned areas and a drag underwater when face-diving into the water at prey. Without constant coastline access (with cool water and cool caves) these cats couldn't live at this extreme climate. At the hottest time of year the majority of their diet may consist of smaller immature squid or prawns hunted at cooler hours. Despite relying on squid as a source of food, they also sometimes fall prey to large mature squid. Closely related cats will alert each other with piercing loud meows (like a small hand-cranked siren) when they see a large squid in the water, but the squid are difficult to see from above. Many go unnoticed. Due to the narrowness of their habitat and the limitations of the food it contains and the cat's ability to catch it, unrelated cats don't like to share beach space and feuds between groups of cats over space and food are common. Fights between coastline cats can get rougher than with inland species as the salt water helps to kill bacteria in their wounds and flush out abcesses, so they can selectively afford to have some cuts and bites without so easily dying of infection. Older cats are often heavily scarred.

Living along the same coastline are West Catland Sand Rabbits (Cuniculus litus) who sometimes use damp dunes and sand banks as some very temporary, but very quick to dig, burrows. These rabbits have a wider range than the coastline cats, finding any firm sandy soil a place to feel at home. However the rabbits closer to the sea enjoy some seasonal seaweed full of nutrients normally not available as much in land plants, boosting health closer to optimal and in turn improving their reproductive chances. As a downaside, the most coastal populations are also slowly evolving an iodine dependency. Such populations are gradually living further South generation-by-generation as the further South they go the more the seaweed availability improves. These rabbits are most recently diverged from a common ancestor with the savannah grassy rabits (Cuniculus herbidus) of further inland. In many ways they are similar, with longer, stiffer legs and a leaner appearance than the ancestral house bunnies, but the sand rabbits have shorter lifespans and reach a much lower maximum size than the grassy rabbits. The coastal cats will make a meal of these rabbits given the chance.

Palm-island Sparrows (Domesticus naufragus) either run through or skim in flight over the water that laps up and down on the sand, looking for small sea animals such as fish, prawns or cockles, especially those that become trapped on land by a receding tide. Their legs and beak are just slightly longer than regular sparrows which helps when they have to dip into the water to find their food. They are versatile sparrows that have learned to exploit a wide range of food sources, and eat inland foods also such as grains and fruit. They are extremely widespread and diverse birds forming a species complex that spans all the Southern coastlines across the globe except Eastern Catland. They have survived many accidental island hopping events, possibly a reason why generally island subspecies are better suited to flight across short distances of sea.

Coconut Sparrows (Domesticus cocoes) are endemic to the West coast of Catland. Although coastal birds they are unsuited to flights over even short stretches of sea. They do have slightly more waterproof feathers through a special hydrophobic dander they constantly shed. Coconut sparrows also have a diverse diet like the Palm-island sparrows, but are more conscious of coconuts from the Coconut Palm (Cocos nucifera) as a food source than other species. They cooperatively chop away at the coconut husks to reach the eye of the coconut that when pecked open releases faintly sweet water that the birds drink from. Because the birds aren't particularly strong they usually only manage to make a small breach to begin with, so they can drink some of it before it drains away. Most is still wasted though. It can save them during particularly dry periods where there is both a lack of food and fresh water. They will also attempt to eat what coconut they can, but rarely can get much unless a whole coconut husk and shell is split from falling on a rock, a rare event. When they find it they make a screech with a pitch that goes up then down to the starting note in a sine waveform, alerting other birds so that they can take alternating turns of feeding and scouting for cats. If they see a cat they make a different sound, the screech incorporated into a chattering stutter that doesn't change pitch much or may slightly rise.