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Autonomous non-profit organization
“Center for Animal Welfare Legal Protection”
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"VETERINARY PATHOLOGY” No 2(17), 2006
Ye.A. Ilyinsky, S.O.Ilyinskaya
(ANO "Charitable Society for the Guardianship of Homeless Animals", Moscow)
DOGS AS DOMINANT PREDATORS IN URBAN ECOSYSTEMS
Introduction
The urban ecological environment is, as a rule, not uniform and generally consists of a set of varieties of natural and anthropogenic landscapes. The problem of stray dogs as the dominant predator in the faunal species composition of natural landscapes that has a limiting impact on various species of the wild fauna is fairly well known and is documented worldwide. This matter is dealt with in many papers of Russian [1-6] and foreign [7-10] researchers. As far as pristine areas of natural landscapes still existing in Moscow are concerned, this problem is portrayed in the Moscow Government document: the Moscow Red Data Book, the first edition of which was published in 2001.
Early in 2004, the ANO “Charitable Society for the Guardianship of Homeless Animals” conducted an expert survey of Moscow nature-conservation institutions that resulted in official responses from such organizations as the national park “Losinyi Ostrov” (‘Elk Island’), “Krylatskie Kholmy” ('Krylatsie Hills'), “Serebryannyi Bor” (‘Silver Wood’) as well as from the Moscow Department of Nature Management and Environmental Protection and Moscow Red Data Book Commission [11]; the responses confirmed there is a serious problem of the adverse impact of stray dogs on the wild fauna of Moscow natural complexes. Suffice it to say that in the “Moscow Red Data Book” stray dogs are referred to as the limiting factor for six species of wild animals entered in the Red Data Book of the city.
Problem statement
However, the problem of interspecies interaction between dogs and cats inhabiting the urban street environment, the so-called homeless dogs and cats, still remains little-studied worldwide. ‘Homeless’ implies all types of street dogs and cats, socially-oriented to man (quasi-unattended, lost, and abandoned) as well as to dog congeners (feral, stray).
It should be noted that the degree of presence of a particular type of homeless animals in the given urban area depends in large measure on the type of ecological environment of the given area, which is related to various way of getting the food (feeding by people, garbage can, hunting) and the different attitude of animals to humans in the neighborhood. For this reason, feral and stray dogs, for example, feeding mainly near the garbage can and by hunting smaller animals, and usually avoiding a direct contact with man, normally inhabit city outskirts and vacant lots. The population density of such animals is much lower in high-rise areas, where the population density of quasi-unattended, lost and abandoned dogs fed by people is, on the contrary, higher.
As for homeless cats, these, being heat-loving, southern creatures (by veterinary standards, cats are to be kept at a temperature not lower than +15 grades on C), their maximum population density is in high-rise areas, where warm basements have become their virtually only refuge. Unlike dogs that in case of an adverse change of the situation (building construction in a vacant lot, removal of garbage cans) can easily change the habitat and in search of a new shelter are capable of covering distances of up to several dozens of kilometers, cats usually cover maximum 100 meters in the urban environment. Often, cats become hostages of their shelter and are reluctant to migrate even when their presence in a basement becomes dangerous to them. It is not uncommon of cats not to be able to move to a different, safer basement of the neighboring building. Therefore, cats are to be given an opportunity to get (or receive) food in close proximity to their shelters.
In the general case, not only each type of homeless dogs and cats, but each individual, by virtue of personal in-born or acquired behavioral complexes, shall have certain specials features of interspecies interactions. However, it seems worthwhile to consider the problem of interspecies interactions in a situation close to reality, where there exists a certain totality of different types of dogs and cats in the urban street environment, and thus to obtain an averaged estimate.
Results of observations
For various reasons, the territory of Moscow proved an ideal ground for studying the problem of interspecies interactions (as stated above) between homeless cats and dogs in dynamic development over a period of several years.
The ANO “Charitable Society for the Guardianship of Homeless Animals” has years of experience conducting its own observations of hundreds of homeless cats living in the conditions of daily contact with stray dogs on the territory of Moscow. Presented in the Table is an aggregate record of monitoring the demise of homeless cats in two Moscow districts. The ecological structure of locality is mixed and comprises most characteristic types of the urban street environment: high-rises, an industrial zone, proximity to natural complexes (in the former case – the Bitsa Park – 900 meters, in the latter case – the Filevsky Park – 150 m).
Because the density of dog population in Moscow since the year 2003 has been unbelievably high, we were able to observe the process of stray dogs hunting homeless cats virtually every day. The interesting thing is that some hordes of stray dogs and even some individuals that were fed by people hunted cats in the daytime routinely. To such dogs hunting was a way of entertainment. The dogs would drive a cat up a tree or under a car and would bark at the poor creature. Besides, sometimes, the dogs would succeed in pulling the cat from under a car by its hind legs. We often saw the wounds left on the hind legs of the discovered cat corpses, as we did so, more often than not, the cat’s belly was rumpled or bitten through. Unlike the fighting pet dogs (Stafforshire terriers or Pit-bulls), which usually strangle cats to death at once, such methods of killing are not typical of stray dogs. Therefore, attacks by stray dogs invariably ended in a long, excruciating death of cats.
While in 2002 and 2003 besides the hordes of stray dogs and stray dogs that hunted cats, there occurred lone dogs that would not touch cats, since 2004, such dogs may be said virtually not to have occurred any more. The reason is they have since bunched up into hordes and have borrowed the cat-hunting skills from other horde members. If there was at least one dog, given to cat chasing, the rest would quickly begin to imitate its behavior as far as cat chasing was concerned.
In addition to the local dogs, just as dangerous were visiting hordes that came deliberately at night from other urban districts to areas of abundant cat population, knowing they could entertain themselves by hunting the cats. The dogs would stay for a long time, laying in wait for cats near the basement air-vents until the cats crawled out for a night walk. Occasionally, such hunters would arrange ambushes on cat’s paths. However, there were particularly sensitive collectively-organized hunting hordes that would split into two parts. One part would sense out and drive a cat into the ambush, in which normally the horde leader stayed; the leader then would make that very jump fatal to the rushing about cat.
Frequently, the dogs would surround the cat pinninging it close to the building’s wall and would bark on it. In such a case, the cat was doomed and could only be saved by a human coming up at a run. While driving away the dogs, we often noticed that the rest of the people were not disturbed by violent barking at their windows and paid no attention.
On more than one occasion, we saw a horde of 4-5 cat-hunting dogs, that were permanently stationed at a considerable distance away, routinely, usually between 2 and 4 a.m., trotting around its regular beat down straight asphalt paths inside the residential areas. The paws of stray dogs are worn out as a result of rubbing against asphalt; therefore the approach of such horde is absolutely noiseless. Seeing a cat, the entire horde, as if on command, would pounce upon the cat with lightning speed. The dogs would not bark in the process, but issued a soft rather characteristic yelping. As the dogs did this, the cat would simply have no time to scream. But, and this is quite typical, too, having rumpled and pulled the cat from jaws to jaws, the dogs would often leave the cat still alive, apparently having lost interest in it, when the cat could no longer offer resistance. Attacks like this often left no avulsed wounds, the belly would not be ripped open, sometimes, and there were even no traces of blood; only a pathologic-anatomic examination, occasionally made by veterinaries of the Center of Molecular Diagnosis of Animal Infectious Diseases indicated injuries of internal organs incompatible with life. It was impossible to save such cats, and they died a few minutes after the attack.
VTSIOM survey
To establish the primary factors limiting the population of street cats in Moscow, the All-Russian Center for the Study of Public Opinion (VTSIOM) conducted a “Survey of the Homeless Cats Situation in Moscow” in July of 2005 [11]. During the survey, interviewed were 372 persons, who act as street guardians of homeless cats and are actually public experts on the problem. The interviewing was done by telephone and was based on a specially prepared questionnaire. The telephone database had been made available by the ANO “Charitable Society for the Guardianship of Homeless Animals”.
Geographically, the survey practically encompassed all districts of the Moscow residential zone. The survey also made it possible to establish the dynamics of the changing homeless cat situation in Moscow as there were three individual periods of homeless cat observations conducted by the guardians: 2003-2005, 2000-2003 and 1995-2000, summing up a decade of observations. It follows from the survey that the number of observed homeless cats during each of the three periods of observation averaged around 20 per respondent.
One of the main objects of the survey was to reveal the basic factors that limit and control the population of street cats in Moscow. According to the survey, the main factor limiting the population of homeless cats over the last 10 years has been extermination of the cats by stray dogs (see the authors’ data in the Table). This factor was referred to as the main one by over 50% of the respondents. Nearly all other people polled indicated that attacks of cats by stray dogs constituted one of the main reasons for the cats’ demise and rated this reason 2nd or 3rd. It follows from the survey that stray dogs attack homeless cats before very eyes of the citizens (see the last column with data in the Table), because 2/3 of the respondents (63%) see stray dogs chasing and attacking homeless cats at least once a month, and nearly one third (28.5%) observe such cases once a week and more often. Among other reasons for the demise of homeless cats, cat killing by man and attacks by pet dogs were cited (these factors were ranked 2). This, after a considerable gap, is followed by the walling up of basements and incidents.
Despite the high percentage of demise, the population of homeless cats has been stable for over 10 years as the deceased cats are superseded by those born in the street and by the abandoned pet cats. Thanks to this, half of the population of homeless cats is renewed during two years.
The ratio of cats born in the street to abandoned pet cats is estimated as 3:2. The average life expectancy of a cat in the street (irrespective of the age at which is became a street cat) is around 1 year. 75% of the kittens of homeless cats that continue living in the street die, not reaching puberty. Around 60% of these kittens die before they are 2 months old as they even never leave their shelters (basements), where they are given birth by homeless cats.
Phenomenon of behavioral inadequacy of cats under stress
While observing the behavior of homeless and pet cats, we managed to distinguish two special forms of cat behavior we termed a phenomenon of behavioral inadequacy of cats under stress (hereinafter, PBICUS): fulminating and lasting forms of PBICUS.
The PBICUS fulminating form manifests itself, more often than not, in a state of panic, loss of orientation, inability to recognize the owner, inadequate assessment of the choice of a safer place, which may cause cat’s demise (e.g. resulting from an encounter with a dog, under the wheels of a vehicle, due to a fall from the balcony). As stray dogs acquire more experience of socializing with cats, the behavior of stray dog evolutionizes whereby the dogs seem to realize that cats possess a relatively low resource of reactive stability. After the dog drive a cat under a car or up a tree, they bark loudly, thereby keeping it in a state of high stress for a while. As they do, some cats have a nervous breakdown in a few minutes, grow panicky and usually try to run for their lives, i.e. may well jump towards the dogs, thus dooming themselves to certain death. Thus, being in an extreme situation, a cat loses the adequacy of behavior, which takes the form of movement from a safe to a dangerous place. The lasting form of PBICUS is manifest mainly in states of depression, apathy, and is characterized by total indifference, sometimes ends in death.
A phenomenon of a most severe nervous stress is common among pet cats which have never been outdoors, especially in a mature age, but found themselves there suddenly (e.g. having fallen off a balcony). Once outdoors, the cats lose orientation completely and lose the ability of recognizing their owners. At the same time, the cats’ stress may be so severe that they can sit motionless for weeks, having hidden in a first shelter that came their way (more often than not, in the basement), until they die of hunger (plunging into the lasting form of PBICUS).
Also, it is not uncommon to observe a situation, where a cat, fleeing from the dogs, does manage to find a refuge and wait there until the attack is over; in this case, the cat is under a most severe stress. This cat, while in a refuge (on a tree, under a car, in the basement) is likely to fall into a state of deep depression and spend a few days in that refuge, shifting to a lasting form of PBICUS . If the stress generated by dogs’ attack is excessive to the extent where the cat’s resources of nervous system rehabilitation, the lasting form of PBICUS ends by death on the spot.
Let us consider an example of the situation when the cat has survived but fell into a lasting form of PBICUS. The cat had lived outdoors for several years, was in the habit of free access to humans, would often sit or walk in an open space, without hiding. After repeated attacks by a horde of stray dogs that had settled in the yard, the cat stopped leaving the basement, but was trapped and taken to somebody’s home. Cat’s subsequent behavior may only be described as total apathy. For several months, the cat was sitting huddled in the same refuge virtually motionless even though nothing in the apartment threatened it. It was only after it made sure there was nobody in the room that it came to the food that had been left beside. If the entrance to the refuge was closed, even with a sheet of newspaper, it did not even try to get out for several days in a row to come up to the food and water, and apparently regarded itself completely isolated and doomed.
There were cases, when a few days prior to demise caused by dogs homeless cats exhibited behavior not typical of them. A cat that had been attacked almost daily by the same horde of dogs suddenly made it a rule to enter the main entrance of a residential building and start mewing loudly for no apparent reason, which it had never done before. The cat was healthy and well-fed. While the cat was mewing, the entrance door stayed open and the barking of the horde of dogs could be heard from afar. The cat died a few days later an excruciating death. The cat had been of cheerful nature. It was unbearable to her to keep hiding in the basement for the rest of its life, coming out for meals only.
The most adroit and agile cats that were attacked dozens of times by dogs, remaining unharmed, displayed a phenomenon that looked very much like suicide. In a situation, when the cats definitely were able to run away from the dogs, they suddenly stopped offering resistance (or lost orientation?) and the dogs killed them. These cats may have been tired of fighting and living in permanent fear. Such behavior may be regarded as a variety of the lasting firm of PBICUS.
Conclusions drawn from conducted surveys
As a result of the surveys conducted in Moscow, the expert questionnaire of the nature-conservation institutions, observations of interspecies interactions between homeless cats and stray dogs, the interview-survey undertaken by VTSIOM, a conclusion has been made that in urban ecosystems the presence of stray dogs as the dominant predator has a crucial and extremely adverse impact on the structure and species composition of the urban fauna, being one of the limiting factors to wild animals and homeless cats. A description is given of cats’ behavior named a phenomenon of behavioral inadequacy of cats under stress.
It is demonstrated that homeless cats, living in a state of a severe predator’s pressing by stray dogs are not only actively destroyed by them, but are forced to overcome a most severe stress and experience a shortage of strengths for re-adaptation from this stress.
Pursuant to the European Convention for the Protection of Pet Animals, humane attitude towards animals manifests itself in the absence of pain, fear and suffering in the animals. In compliance with this doctrine and taking into consideration the results of the conducted survey, it may be concluded that conditions under which pet animals, i.e. cats and dogs, not attended to by their owners or born in the street, have to live side by side with one another, sharing the same territory, do not meet the requirements of humaneness.
APPENDICES:
1.Tables of monitoring homeless cats’ demise ;
2.Pathologic-anatomic examinations of cats killed as result of attacks by stray dogs:
Pathologic-anatomic examination No 1
Pathologic-anatomic examination No 2
Pathologic-anatomic examination No 3
Pathologic-anatomic examination No 4
Pathologic-anatomic examination No 5
Pathologic-anatomic examination No 6
References:
1. Ryabov L.C. Stray and feral dogs in Voronezh Region. Bull. MOIP. Bull. Div. Moscow, 1979, v. 84, issue 4.
2. The Impact of anthropogenic landscape transformation on population of land vertebrates. Theses of All-Russian Meeting. Moscow, 1987.
3. Novikov G.A. Fundamentals of general ecology and nature conservation. Leningrad, LGKh 1979
4. Animals in the city. Coll. Trans. Of Scient.-Pract. Conf. MSKhA/IPEE, 2000-2003, v. 1-2.
5. Wagner B.B., Zakharova N.Yu. Animals of Moscow Region. Moscow: "Moskovsky Liceum ", 2003.
6. Krasnov Yu. Tender domestic killers. National game journ. “Hunting”. 2005, No 9
7. Denney R.N. The impact of uncontrolled dogs onwildlife and livestock. Trans. North. Amer. Wildl. and Nat.Res.Conf.l974?39.
8. Jeffrey S., Philip S. Feral Dogs, Prevention and con trol of wildlife damage. Great Plains Agricultural Council, Wildlife Com. and oth. 1994.
9. Kreeger T.J. Impact of Dog Predation on Minnesota Whitetail Deer. The Minn. Acad. Sci. 1977, vol. 43.
10. Domestic Dogs as Predators on Deer. Wildlife Society Bulletin. 1978, vol. 6, No. 1.
11. Collection of documents and materials on information internet site of the ANO "Charitable Society for the Guardianship of Homeless Animals". http://www.AnimalsProtectionTribune.ru
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