What is a Frugivore?

The term “frugivore” is used to describe animals who have evolved to eat fruit as their primary food. The word “frugivore”, which comes from Latin, means “fruit” and “vorare”, to consume or devour. Frugivores eat fruit.

It is considered a type of herbivory because it involves the consumption of plant material. Frugivores are different from other herbivores who eat leaves, stems or roots. They eat the reproductive parts, such as fruits, which contain sugary pulp.

They can use fruit as food because of their specialization. Fruit is available only during certain seasons and in large quantities. Sugars are essential for frugivores.

Fruits were also created to be eaten in order to aid seed dispersal. Frugivores are essential in spreading seeds away from the parent plant, which encourages biodiversity and forest regeneration.

What is a Frugivore?

A frugivore is an animal that consumes more than 50% fruit in its diet. Some frugivores, called “obligate frugivores,” eat only fruit. Some frugivores are called “generalists,” because they eat fruit, but also other foods like leaves, insects or nectar.

True fruit lovers prefer ripe, nutritious fruits that are packed with sugars easily digestible. Green unripe fruit should be avoided as it is less nutritive and contains more toxins. Fugivores migrate to or target specific plants as certain fruits ripen in cycles of fruiting season. This allows fruit seeds to be dispersed far away from the plant.

Even animals who don’t consume more than 50% of their diet in fruit are important seed dispersers and fruit consumers. Tapirs, elephants and hornbills eat leaves but fruit can make up 30-40% or more of their diet when fruiting. These animals help disperse seeds over long distances. This is very beneficial to plants.

Fugivores, then, are animals that specialize in ripe fruits. They can be found in a variety of habitats. However they thrive most in tropical areas. They play a vital ecological role by spreading and consuming the seeds of fruiting plants.

The types of frugivores

The size, texture and accessibility of the fruit determines which frugivores are best suited for dispersing seeds. The following are the main types of frugivores, grouped by taxonomic group:

Mammals

Worldwide, mammals make up the majority of frugivores.

• Primate species like lemurs and monkeys are primarily frugivorous. They feed on fruits that hang in the canopy of rainforests. They can detect and pick up ripe fruits with their excellent color vision.
• Another important group of frugivorous mammal is the bat. Fruit bats have excellent vision and smell to locate ripe fruits, just like flying foxes. They can disperse their seeds further than other frugivores because of their ability to fly.
• Fruit is a major source of food for certain rodents. These include squirrels, tree-shrews and rats. To find ripe fruit, they use their climbing skills and keen senses. The caching of fruits helps to disperse seeds.
• Sun bears and spectacled bears are among the bears that feed heavily on fruit, particularly during seasons of abundant fruits. They can eat large amounts of seeds and pulp, and transport seeds long distances because of their size.
• Civets, a medium-sized mammal that eats fruits such as figs and palms, are able to climb and ingest them. Possums, potoroos and rat kangaroos are also frugivorous mammal species.

Birds

Fugivory is a major role played by many tropical bird species.

• Toucans, and Hornbills, have large, specialized beaks that are ideally adapted for reaching, picking, and processing large fruits. Their powerful wings spread the seeds they ingest.
• Parrots have strong hooked beaks that they use to reach protected fruits. Their intelligence allows them to locate fruit crops that are ephemeral and disperse seeds by flight and caching.
• All tanagers and cotingas eat fruit to disperse their seeds.
• High-mobility nectivorous bird, like sunbirds or hummingbirds, also eat small fruit. This helps pollinate and disperse seeds between isolated plants.

Reptiles

• Some reptiles are also frugivorous. Iguanas have dewlaps that help them collect and digest fruits. Tortoises such as the Aldabra Giant tortoise eat fallen fruit and carry seeds long distances. The robust digestive system of the Aldabra giant tortoise allows seeds to pass unharmed.

In essence, mammals, birds and reptiles of all sizes, from mice to massive apes, use fruit resources with specializations. It is possible to spread the seeds of many plants far and wide. This ensures their survival and propagation.

The Characteristics Of Frugivores

Fugivores are adapted both physically and behaviorally to be able detect, access and consume fruit efficiently.

Physical Adaptations

To be able consume so much fruit, frugivores need certain senses and abilities.

• Fugivores benefit from excellent color vision to distinguish between the vibrant colors of ripe, nutritious fruits and green unripe fruit. For this reason, many primates and birds possess trichromatic colour vision.
• Fugivores can detect the aroma of ripe fruits using their fleshy or sensitive noses. They can find fruit even from afar.
• Ability to digest large amounts of simple sugars, carbohydrates and other substances in pulp and ripe fruits flesh. Some frugivores have even enlarged livers in order to process excess fructose.
• Arboreal species such as monkeys have bodies that are adapted to climbing, which helps them reach fruit in the canopy of the forest. In birds, the wings allow them to reach fruits that are located on tall or isolated trees.
• The lightweight build of species such as gliders and bats allows them to reach fruiting branches on the periphery. Some monkeys have prehensile tails that allow them to grasp additional fruit.
• Animals like tapirs and nectar bats use their long tongues and bills to grab tubular or protected fruits.
• Animals like bats and bears have large fat reserves that store energy after a season of fruit eating.

Behavioral Adaptations

Fugivores are characterized by complex behaviors that revolve around the consumption of fruit.

• determining ripeness using visual and olfactory clues is important, since frugivores avoid unripe fruit or spoiled fruits.
• Predicting and following fruiting cycles, phenology patterns and target specific fruiting plants and trees during their peak fruiting period.
• Fugivores can remember the locations of fruits from previous years using spatial memory and cognitive maps.
• When fruiting crops are restricted, aggressive displays and competitive displays can be used to establish the feeding rights. However, other frugivores may display symbiotic relationship and alert their mates to fruiting.
• Dispersing seeds through defecation or spitting/regurgitation away from the parent plant gives offspring an improved chance of survival without competition.
• If you are under pressure, swallow the fruits whole and slowly digest them over time.

The adaptations of frugivores are impressive, allowing them to specialize and depend on the ephemeral fruit resources.

The role of frugivores is seed dispersal

Fugivores are important ecological agents because they disperse seeds. They act as mobile seed dispersers by consuming fruits and passing the seeds through their digestive systems.

The following mechanisms are used to provide immense value to both forest ecosystems as well as human agriculture by this seed dispersal service:

• The offspring can access new habitats, away from competitors, by defecating and regurgitating seeds. This promotes forest regeneration by expanding the range.
• Ingestion and intestinal passage can remove the fruit pulp from the seeds and scarify them, which increases the rate of germination.
• Manure is applied to seeds that have passed through the digestive tract. This fertilization boosts growth and germination.
• The seeds are spread over vast distances by frugivores that travel widely, such as hornbills or large mammals. This allows for long-range colonization. This helps maintain connectivity between forests that are fragmented.
• Frugivores create ideal conditions for germination by defecating directly onto moist soil in shaded areas, away from dense roots competition. This boosts the recruitment of seedlings.
• The seeds are carried by fuguvores to areas where new growth is possible, such as disturbed patches, gaps in the forest, riverbanks, trails, and places with ample light. This encourages forest patches and diversity in succession.

In essence, frugivores act as mobile links that enable plants to disperse their progeny from the parent tree. This promotes ecosystem resilience, biodiversity and regeneration in tropical forests.

Frugivores and Seed Dispersal Services

These are some notable examples of frugivores that disperse seeds.

• Tapirs disperse large quantities of seeds, such as palm fruits, through the jungle. This allows the plants to grow far beyond their existing stands.
• Hornbills and Parrots transport seeds for a distance of dozens of kilometers in their gut and beak. This is an important method for long-distance distribution.
• Like flying foxes they can disperse fruit seeds up to 50 km by defecation and flight. This allows plants the opportunity to colonize and expand their ranges.
• The feces of bears and monkeys, which contain intact seeds, act as a fertile nursery patch that provides seedlings with nutrients and protection. This greatly improves germination.

Tropical plants are therefore heavily dependent on frugivores to disperse, increase offspring success and maintain connectivity in fragmented landscapes. Fugivores are therefore key ecological players for maintaining healthy, biodiverse rainforests.

Frugivores: Examples and Diets

Fruit-lovers around the globe consume many different fruits depending on their environment and seasonal availability. Here are some examples:

Howler Monkey 

Howler monkeys eat ripe fruit to a high percentage. Fruits high in energy like figs and mangoes are preferred. Their diet is mainly composed of young leaves, flowers and nuts, as well as insects, eggs and small vertebrates. Their color vision, intelligence, and dexterity help them to target ripe fruit.

African Elephant

African Elephants are megaherbivores who eat leaves, stems and bark as well as grasses. They also eat a lot of fruit. Fruits can make up over half of their diet when fruiting season is in full swing.

Through long-distance transportation and consumption, they disperse heavy, large seeds, which play a key role in the propagation of massive trees such as marulas and baobabs across Africa.

Bear Spectacled

The spectacled is the last surviving bear in South America. It lives in the Andean clouds forests and feeds on bromeliads and orchids as well as fruits of trees such Podocarpus and Pourouma.

Its varied diet comprises between 40-60% ripe fruit. Fruit is its main source of food, especially in times when other sources of vegetative foods are scarce. This threatened bear is vital to maintaining the diversity of Andean Cloud Forest. It is the only native disperser for some plants.

Red Whiskered Bulbul

The red-whiskered Bulbul is a tropical songbird that has been widely introduced around the world. Its diet is made up of fruits like bananas, papayas, mulberries and grapes. Also, it supplements its diet with small insects and nectar.

It spreads invasive plant seeds. In its native Asia it disperses native fruits seeds and plays a positive ecological role.

Flying Fox

Fruit bats and flying foxes play a vital role in dispersing seeds. Fruit pulp and nectar, such as those from figs, mangos, guavas, and cashews, make up over 90% of their diet. They have a remarkable ability to disperse seeds because of their mobility, sharp senses and the ability to digest hard seeds. Fruit bat loss is a disaster for agriculture and tropical forest regeneration.

Diverse frugivore species depend to different degrees on fruit types based on their habitat. They almost all perform the crucial ecological service of dispersing seeds, which makes them essential to maintaining biodiversity, connectivity and productivity in tropical ecosystems.

The Threats to Frugivores

Due to the following human-made threats, there are population declines and even extinctions of many frugivores species around the world.

• Deforestation is widespread for agricultural and timber purposes, destroying frugivore habitats. This also eliminates their resources for foraging. For  example, over 90% fig tree species are threatened in Borneo by palm oil plantations.
• Commercial bushmeat hunts in tropical rainforests decimate frugivorous apes and monkeys. Lemurs and duikers are also affected. Trees depend on these animals for their dispersal. In Ghana, hunting reduced monkeys by 90% in just four decades.
• Wild parrots and monkeys are captured for exotic pet trade. The removal of fruit-eating animals from their native habitats is a serious threat to the environment.
• The culling of bats, elephants and birds that are vital for the spread of native seeds is a result of farmers treating them as pests.
• Invasive species such as rats compete with and prey on endemic island frugivores. This leads to their extinction. Invasive predators have wiped out most native Hawaiian frugivores.
• Climate change disrupts the distribution of plants and their fruiting cycles. Fugivores who depend on seasonal fruit are affected by the loss of synchronicity.
• Humans overharvest wild fruits, leaving little for frugivores. Shea and mango harvested for the global market in an unsustainable manner impacts local wildlife.

The world’s frugivores face a number of threats. The loss of these animals will be devastating for tropical forests that depend on them for regeneration and diversity via long-distance seed dispersal. It is essential to take immediate action in order to preserve the important ecological interactions that exist between plants and frugivorous animals.

Conserving Frugivores

Diverse conservation strategies are required to conserve Earth’s frugivore population.

• Protection of existing habitats, fruit sources, and protected forests through established parks, protected forest, and reserves. These protected areas are home to healthy frugivores and a wide variety of fruits.
• Maintaining habitat connectivity by establishing conservation corridors and buffer zones to allow frugivores access to multiple fragments. Hornbills were able to restore plant interactions lost between Indian forest fragments by using corridors.
• The imposition of hunting restrictions and bans to allow the recovery of overexploited frugivores. The Costa Rican forest was able to regenerate after the primate hunts were banned.
• To boost ecosystem function, captive breeding and reintroduction programmes can be used to restore critically threatened frugivores such as the Golden Lion Tamarin.
• Orchards of alternative fruit trees can be planted on farms as a way to divert animals from destroying crops. Orchards have reduced elephant raids on crops in Sub-Saharan Africa to over 80%.
• Integrating fruit trees into farmland is a form of agroforestry. It provides frugivores with habitat and nutrition, while also providing a variety of services to farmers.
• Implementing biological educational programs to highlight the importance of frugivores in healthy forests and for human welfare, through ecosystem services.

The protection of frugivores should be a priority in conservation because their loss can lead to the breakdown vital ecological processes such as gene flow, forest regeneration and carbon storage via seed dispersal. This collapse has devastating cascading effects on ecosystems and human wellbeing.

The conclusion of the article is:

The frugivores are a group of diverse fruit-eating mammals with special adaptations that allow them to consume and disperse seeds while also consuming fruits. Frugivores are primarily fruit-reliant and provide an important ecosystem service by dispersing seeds to many different plants throughout tropical forests. This dispersal promotes gene flow, range extension, forest regeneration and biodiversity.

However, frugivores are increasingly imperiled globally by an onslaught of anthropogenic threats. The loss of these important seed dispersers is a disaster for tropical forest and human welfare.

To ensure their survival, conservation efforts that focus on frugivores and their habitats as well as their food resources are necessary. It is essential to maintain resilient and biodiverse rainforests in the face of global change pressures.