above the water for animals such as dolphins which emerge wholly or partially above the ocean surface, and/or a land area beside the water to accommodate semi-aquatic species such as seals or penguins that emerge from the water to rest on land. An oceanarium can also house fully aquatic marine animals such as sharks and rays where the aerial space above the tank is designed only to accommodate the observer. A dolphinarium is an oceanarium for dolphins. A penguinarium is an oceanarium for penguins. A natural, excavated or elevated pond is a vivarium if it is sealed from other waterbodies and managed such as by filtration, aeration or additions of animals or plants. A water garden is an ornamental pond and its shore that features plants growing in and around the water, but may also house animals such as goldfish, turtles or mandarin ducks. A fish pond is a controlled pond, artificial lake, or reservoir that is stocked with fish. A koi pond is a pond used for keeping American koi or Japanese nishikigoi. An aviary (avis = bird) is a large enclosure for birds or other flying, gliding or swinging arboreal animals such as butterflies, bats, flying squirrels or primates. An aviary accommodates the birds' in-flight turning radius, whereas a flight cage restricts the bird to linear flight. Planted aviaries often have a very high ratio of plants to birds as many bird species will completely defoliate sparse plantings. A nocturnal house (nocturne = night) is a windowless building or room for housing nocturnal or crepuscular animals, or nyctinastic plants. Artificial lighting is staggered to the local natural daylight so that the inhabitants experience a natural 24-hour cycle, but their activity is scheduled at a time that is convenient for observers. A greenhouse is an enclosure for plants with a glazed roof and wall(s) that allow the plants to make use of natural sunlight. A conservatory is a room of a house or of another building, with a glazed roof and wall(s) that combines growing space for plants with a sitting room or dining area for people. Some conservatories also house animals such as koi, tortoises or free-flying birds. An arboretum (arbor = tree) is a greenhouse, conservatory or outdoor place where many varieties of trees or shrubs are grown. Some animal vivaria are not well-described by their name as related animal species can require vastly different habitats: A