The success of an animal fable depends on the ability of the writer to tell a story on two levels at once. To capture and maintain the reader’s interest, the story needs interesting events in a concretely presented secondary world. To become significant and memorable for the reader, the story must speak to human needs and human concerns. Adams uses several techniques to achieve the first of these objectives, making his secondary world seem real.

A close observation of the plants and animals of the English downs informs the story, and all the details of nature are seen from a rabbit’s-eye-view; the reader may find freshness and sharp reality in even the familiar daisy when the flower is seen from that unusual perspective. Part of the theme of the story is that human perspective is not the only one from which the earth is seen.

Like J. R. R. Tolkien in The Lord of the Rings (1954-1955), Adams uses invented languages to present Watership Down from these unique viewpoints. Not only do the rabbits have their own language, words of which the reader encounters from time to time, but also rabbits from different regions speak various dialects. The other animals of the downs have their own languages, as the characters from the warren discover when they meet a field mouse and a seagull. Adams employs his rabbit language not merely as an exotic detail but to reveal further insights into rabbitkind, as an analysis of the word hrair shows. First, since rabbits can conceive of numbers only up to four, larger numbers are expressed as simply “a lot” or “many,” and this is one of the meanings of hrair. Next, when a litter of rabbit kittens numbers more than four, the fifth—or runt—of the litter is likely to be named hrair, hence the name of Hazel’s brother, translated into English as “Fiver,” a name expressive of his small size and status. Again, hrair in its meaning of “the many” may be used to stand for all those animals that prey upon rabbits, and in this sense it is translated as “the Thousand.” Finally, in the name “Prince El-ahrairah,” the word hrair translates as part of a title, “the Prince with a thousand enemies.” The interweaving of the lapin language is skillfully and consistently worked into the plot, serving organically as one part of Adams’ secondary world.

In this secondary world, the story reveals a deep affection for the ordinary little creatures of the downs. There is no denying that human ideas of progress are often shown in an unfavorable light. Yet Watership Down is not simply an “ecological” story, one which shows humans only as despoilers of nature. All the themes of the story are presented from the rabbits’ viewpoint, and the humans who figure as accessories to the plot are always pictured through the consciousness of the rabbits, to whom humans and their works are simply inexplicable natural phenomena. At one point in the story, the appearance of an express train saves some of the rabbits from catastrophe, an event they interpret as divine intervention. Although humans set the action of the story in motion by destroying Cowslip Warren to make room for a subdivision, the rabbits feel no personal animosity toward the humans, whom they perceive as simply indifferent to the rabbits’ survival.

The Natural World and Development
A major concern in the book is the devastation of the natural world that results from human development of the land. The book's action begins when humans post a notice in the field where the rabbits live; it reads:

THIS IDEALLY SITUATED ESTATE, COMPRISING SIX ACRES OF EXCELLENT BUILDING LAND, IS TO BE DEVELOPED WITH HIGH CLASS MODERN RESIDENCES BY SUTCH AND MARTIN, LIMITED, OF NEWBURY, BERKS.

In a harrowing chapter, one of the two survivors of the poisoning and bulldozing of the rabbits' home warren tells of the cold destruction, and the rabbits' realization that the humans killed them, as another rabbit said, "just because we were in their way. They killed us to suit themselves."

Throughout the book, the rabbits are keenly aware of humans and their disastrous effects. When they cross a road, Adams vividly describes the disgusting smells of cigarettes, tar, gasoline, and exhaust, as well as the rabbits' nauseated response to them. The cars on the road can run faster than any rabbit—something highly unnatural—and when they pass a rabbit, they don't seem to notice the rabbit at all. Machine-like, they stay on the road, and machine-like, they don't slow down for animals. This lesson of human senselessness and lack of connection or care is borne out by the presence of a smashed piece of roadkill—a hedgehog that is now "a flattened, bloody mass of brown prickles and white fur, with small black feet and snout crushed round the edges."

Humans are associated with this senseless, machine-like response to the world, which leads to callous death; they are also associated with some of the worst enemies of rabbits: cats and dogs. In contrast, Adams lovingly and vividly describes the natural world in great detail. Almost every page of the book contains passages on nature that are as vivid as those written by any naturalist and that allow the reader to step into the rabbits' world. In fact the book begins, "The primroses were over. Toward the edge of the wood, where the ground became open and sloped down to an old fence and a brambly ditch beyond, only a few fading patches of pale yellow still showed among the dog's mercury and oak-tree roots. On the other side of the fence, the ground was full of rabbit holes...."

Throughout the book, descriptions of natural beauty and rabbit life are contrasted with the disastrous effects of humanity. The first warren is utterly destroyed by development. Cowslip's warren, where the rabbits are fat and leisurely, is owned by a farmer, who kills rabbits to sell for meat. Efrafa, the totalitarian dictatorship, became that way partly in response to hazards—if humans didn't know the rabbits were there, they couldn't kill them, so General Woundwort instituted an increasingly repressive series of controls to keep the warren a secret. Kehaar the seagull is wounded by a farmer's pet cat, and so is Hazel.

The rabbits' only chance for permanent safety lies in getting as far away from humans as possible—to the remote, high country of Watership Down. What Adams does not bring up is the question of whether increasing development will eventually reach even there—if the rabbits' safe home will one day, like the first warren, be destroyed to make way for human building.

Democracy versus Totalitarianism
The book clearly contrasts two forms of leadership—democratic versus totalitarian. Under Hazel's leadership, discussion, openness, and equal participation among all members of the warren is encouraged. In the closed warren of Efrafa, General Woundwort's word is law, and any discussion is immediately punished.

In Efrafa, each rabbit is "marked," and its behavior is strictly regulated; as Holly explains, "They bite them, deep, and under the chin or in a haunch or forepaw. Then they can be told by the scar for the rest of their lives. You mustn't be found above ground [to feed or excrete waste] unless it's the right time of day for your Mark." Each Mark has a captain who oversees this and punishes infractions, and if a Mark can't go above-ground because a man or a predator is near, it must wait until the next day. To prevent the spread of infection—and dissension—rabbits are not allowed to visit another Mark's burrows without permission, which is seldom granted.

The warren's Owsla, or police, patrol the countryside, watching out for predators. When they find strange rabbits, they bring them back to Efrafa or, if they won't come back, kill them so that they don't attract the attention of humans or other predators to the area.

Supposedly, this system arose because General Woundwort, who took control of the warren, wanted to ensure its safety from predators. However, in exchange for safety from outside enemies, the rabbits now are constantly threatened and oppressed from within, by those in power. As a result, most of the rabbits in the warren can't do anything but what they're told to do; they've never been out of the warren, never smelled an enemy, and never learned to think independently.

Those who do think independently are severely punished. In a chilling incident, Bigwig meets Blackavar, a rabbit who tried to leave Efrafa. Guarded by rabbit officers, he stands at the entrance to a burrow, where all can see him. As Adams writes, "He was dreadfully mutilated. His ears were nothing but shapeless shreds, ragged at the edges, seamed with ill-knit scars and beaded here and there with lumps of proud, bare flesh. One eyelid was misshapen and closed askew." He has been held here for a month, forced to explain to all who ask that this torture and mutilation was his punishment for attempting to leave, and thus instilling fear and obedience in other possible rebels.

The concern for the environment and the focus on leadership combine to form the central theme of the novel, which is the formation of community. In the lapine world of Watership Down, community results when a group of individuals share a common purpose in life, realize that cooperation is essential to survival, and trust the complementary talents of others.

The plot allows these issues to be surveyed from a variety of perspectives. The story begins in the threatened warren, Sandleford. It is an ordinary society, pleasant but imperfect, neither an Eden nor a tyranny. Its doom comes from without, not within; only a half-dozen rabbits, sensing some ill-omen, flee the warren and survive its destruction. Now in a hostile environment, the band, led by Hazel, must rebuild community even as it moves. To survive, the group pools its wisdom, and each individual takes responsibility for what he does best: The fastest scouts ahead, the biggest confronts enemies, the most cunning chooses a place to rest.

The wandering escapees of Sandleford encounter two other societies. Cowslip warren at first seems delightful: Its rabbits are well fed and uncrowded. Its bounty is deceiving, however; the warren survives only as a farmer's colony, well fed in order to provide an occasional, inevitable stew to the man's table. The Cowslip rabbits understand their plight, but lack the will or wisdom to combat it.

If Cowslip warren is pampered and imprisoned, Efrafa warren is fiercely independent. To preserve itself, however, Efrafa has developed a militaristic, fascist state under the rule of a ruthless, ever vigilant leader. Efrafa lets no native rabbit leave and enslaves outsiders who wander into its territory.

When the Sandleford refugees establish their own warren at Nuthanger Farm on Watership Down, they preserve the freedom that Cowslip surrendered in exchange for ease, and they find the solidarity that Efrafa could impose only by force. Adams remarked once that he strives to portray an "animality" which corresponds to "humanity" — i.e. those ground rules which harmonize the competing interests of the individual and the group. Watership Down argues that cooperation, self-control, and self-sacrifice are as crucial to animality as to humanity.