Natural History of Vampire Bats

Arthur M. Greenhall

• Publisher: CRC Press
• Year: 2018
• Print ISBN: 9781315895819
• eBook ISBN: 9781351091817
• Edition: 1
• Topic: Medicine
• Subtopic: Veterinary Medicine

A major problem with vampire bats is that whatever information exists is scattered throughout the literature or is not recorded. There are some excellent books on the ecology and biology of bats with very little on vampire bats. This volume fills that gap to provide an in-depth presentation of these unique animals.

Chapter 1

INTRODUCTION TO THE NATURAL HISTORY OF VAMPIRE BATS

Merlin D. Tuttle

INTRODUCTION

Known to all, understood by few, the common vampire has long remained a mysterious enigma. Its unique blood feeding habits were vividly reported as early as the 16th Century, but the exact identity of the animal was not confirmed for more than 200 years. Early biologists erroneously applied vampire names, ranging from Vampyrops to Vampyressa, to at least five other genera, mostly fruit and nectar-eating bats, but taxonomic descriptions of Latin America’s true vampires, Desmodus rotundus, Diaemus youngi and Diphylla ecaudata, were not complete until the early 20th Century. Vampires remained scientifically neglected until one, the common vampire, Desmodus rotundus, was implicated in a rabies outbreak in Trinidad in the 1930s.¹

A flurry of study confirmed that this bat was the principal vector,² leading to intensive research, mostly aimed at control.^{3, 4} Meanwhile, widespread anti-vampire campaigns included dynamiting, poisoning, and burning of bat roosts in general.⁵ More than 8,000 caves were poisoned and/or dynamited in a single country, needlessly eliminating entire ecosystems of unique cave life and killing countless thousands of highly beneficial bats.⁶

Much more effective techniques eventually were developed (See chapter by R. E. Lord). These included wound treatment with strychnine, anticoagulant pasting of captured vampires, and intrarumenal injection of an anticoagulant into victimized cattle.⁴ With appropriate education, such solutions to vampire problems have proven very helpful. Nevertheless, funds for vampire research were largely eliminated soon after the development of effective control methods and vaccines. Lacking funds, essential knowledge of technique application often was not implemented at the local level.

Many field workers were not adequately trained, either in vampire identification or in technique application.^4,7 In one country, McCarthy⁷ did not find a single vampire among voucher specimens saved during pasting of so-called “vampires”. The misidentified bats were all beneficial species, needlessly killed. In another country, he reported that untrained military personnel were assigned to vampire eradication.

Widespread misapplication of vampire control continues, as illustrated by responses to a rabies outbreak in Central America. Although some articles in local papers stressed the importance of proper vampire identification, they referred to all bats as various kinds of vampires and listed identification characteristics that were highly misleading.⁸ For example, drawings contrasted bats with and without noseleaves, implying that any bat lacking a noseleaf was a vampire. This ignores the fact that most of Latin America’s insectivorous bats also lack noseleaves. One article even included a photograph of a small Asian flying fox as an aid to vampire identification!⁸

Recommended control procedures included poison baits, burning hollow trees, suffocation by smoke at roosts, electrocution, and vampiricide paste applied to netted bats.⁹ Given the extent of misleading advice, it is unlikely that even the vampiricide paste would have been used correctly. Roosts were burned, and bats killed indiscriminantly.¹⁰

Attempts to kill vampires with poisoned fruit also persist. Personnel on one ranch treated stalks of ripe bananas to kill vampires and were convinced of their success when dead fruiteating bats were found.¹¹

Such problems of misidentification and indescriminate control are not surprising when one considers that, even outside Latin America, people are far more likely to know about vampires than about beneficial species. In fact few people anywhere know that there are nearly 250 species of bats in Latin America,^{12, 13} making up over half of all mammal species there, or that the vast majority are highly beneficial. Just three are vampires, and only one of these causes substantial economic harm. Unfortunately, since the beneficial activities of other Latin American bats are seldom studied or publicized, people there are left with the erroneous impression that most bats are vampires or at least harmful.

In reality, less than one bat in thousands is a vampire. Some 70% eat insects, and these are the most important natural controls of night flying species,¹⁴ including such pests as mosquitos.^{15, 16, 17} A single bat can catch 500 or more insects in an hour,^{17, 18} and large colonies eat tons nightly.¹⁹ Equally important are the seed dispersal and pollination activities of fruit and nectar-eating bats that are vital to the survival of rain forests and reforestation of cleared areas.

Huber, an early botanical explorer of Brazil, concluded that bats were the most important of all seed dispersal agents in the Amazon,²⁰ and Fleming and Heithaus²¹ and Janzen^{22, 23, 24} showed how seed dispersal by bats may increase seed survival by more than just removing them from the vicinity of the parent tree. In West Africa, Thomas²⁵ found that seeds dropped by bats account for up to 95% of forest regrowth on cleared land, and in Latin America as well, many of the most important woody pioneer plants rely on bats for dispersal,^{26, 27} as illustrated by recent studies from Costa Rica²⁷ to French Guiana^{28, 29} and Peru.³⁰ Although a large proportion of bat-dependent plants undoubtedly have not yet been reported, approximately 250 genera already are known to rely on bats to varying degrees for pollination alone.³¹

Flowers of many tropical and subtropical plants open only at night, produce special odors and are mechanically adapted to facilitate bat pollination.^{31, 32, 33, 34, 35, 36, 37, 38} In fact, some are so dependent on a single bat species that the relationship has been compared to a “lock and key”.³⁹ Myers⁴⁰ referred to such bats as “keystone species” and noted that if one of these pollinators were to be eliminated, “the loss could trigger a cascade of linked extinctions”, with shattering effects throughout an entire ecosystem.

Gardner²⁶ provides an extensive list of Latin American plants that are visited by bats. Many of these and others are of great ecological and/or economic importance and highly reliant on bat visitation in the wild. Just a partial listing includes valued fruits, spices and nuts, from avocados, guavas, star apples, and sweet and sour sops, to cloves and cashew and sapucaia nuts. Other products include palm hearts and oils, local wines, fishing bait, canoes, balsa and other prized timber, kapok, and even tequila liquor.

It is highly unfortunate that the vast majority of Latin American studies involving the economic impact of bats have concentrated solely on damage done by the common vampire, while largely ignoring the very substantial contributions of other bat species. On balance, the economic benefits derived from the majority likely far exceed the widely publicized millions of dollars of losses attributed to vampires. Nevertheless, without substantially greater research balance, combined with extensive education at all levels, many of Latin America’s most beneficial bats may be reduced to economically and ecologically inconsequential numbers long before their vital importance can be appreciated.

The common vampire is generally scarce away from man and his livestock.⁶ Populations are now unnaturally large, undoubtedly having benefited from human arrival, notwithstanding man’s best attempts at eradication. This is in sharp contrast to the fate of many beneficial bat species that are much more v...

Table of contents

• Cover
• Title Page
• Copyright Page
• Table of Contents
• Chapter 1 Introduction to the Natural History of Vampire Bats
• Chapter 2 Systematics and Distribution
• Chapter 3 Paleontology
• Chapter 4 Genetics
• Chapter 5 Anatomy
• Chapter 6 Locomotion
• Chapter 7 Social Organization and Behavior
• Chapter 8 Reproduction
• Chapter 9 Feeding Behavior
• Chapter 10 Salivary Antihemostatic Factors
• Chapter 11 Orientation and Sensory Function in Desmodus rotundus
• Chapter 12 Transmission of Pathogenic Microorganisms by Vampire Bats
• Chapter 13 Parasites of Vampire Bats
• Chapter 14 Economic Losses due to Desmodus rotundus
• Chapter 15 Control of Vampire Bats
• Chapter 16 Care of Vampire Bats in Captivity
• Chapter 17 Man, Gods, and Legendary Vampire Bats
• Index