Daniel Haag-Wackernagel - Academia.edu (original) (raw)
Papers by Daniel Haag-Wackernagel
... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gme... more ... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gmelin 1789) in beinahe jeder Stadt zu-genommen. ... Gesundheitsgefährdungen durch die Straßentaube Columba livia: Parasiten Daniel Haag-Wackernagel ...
Annals of agricultural and environmental medicine : AAEM, 2004
The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus c... more The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus columbae) over a period of 2 months. The source of the fleas was a pair of breeding feral pigeons (Columba livia). The birds' nest was located in the attic immediately above the couple's apartment, and the fleas found their way along an unsealed heating pipe. The people encountered up to 40 bites per night. With invasions repeated almost every night, the man gradually developed an allergic urticarial reaction. The most traumatic experience for the couple, however, was to learn that they were invaded by fleas (initially, they had presumed they were bothered by mosquitoes). This information resulted in severe psychological distress with phobic reactions and insomnia. Despite the successful removal of the fleas and the pigeons that were source of the pest, parasitophobia of the man persisted over the following 4 months. This case is discussed from the broader aspect of health risks r...
Berliner und Munchener tierarztliche Wochenschrift, 2015
We examined 80 feral pigeons and their fecal samples from two feral pigeon lofts of the "Pig... more We examined 80 feral pigeons and their fecal samples from two feral pigeon lofts of the "Pigeon Action of Basel" (Switzerland) for different pathogens. The tested material harbored four pathogenic agents transmissible to humans (Chlamydia spp., Salmonella spec., Campylobacter jejuni, Cryptococcus neoformans) In addition several pathogens were found which are no zoonotic agents but potentially pathogenic for the pigeons themselves, such as Trichomonas gallinae, coccidia, helminths, ectoparasites and fungi. The number of pathogens and parasites detected in the fecal samples varied significantly between the two localities. The pigeons of the two investigated breeding flocks differed in nutritional status and the incidence of two species of feather lice, Columbicola columbae and Campanulotes bidentatus compar. The prevalence of Trichomonas gallinae between juveniles and adults was not significantly different but juveniles exhibited significantly heavier infestation if infected...
Es wurden 80 Strasentauben und Kotproben aus zwei Strasentaubenschlagen der „Basler Taubenaktion“... more Es wurden 80 Strasentauben und Kotproben aus zwei Strasentaubenschlagen der „Basler Taubenaktion“ (Schweiz) auf das Vorhandensein verschiedener Krankheitserreger untersucht. Dabei wurden vier auf den Menschen ubertragbare pathogene Mikroorganismen gefunden (Chlamydia spp., Salmonella spp., Campylobacter jejuni und Cryptococcus neoformans). Daruberhinaus fanden sich auch Krankheitserreger ohne zoonotisches Potential wie Trichomonas gallinae, Kokzidien, Helminthen, Ektoparasiten und Pilze, die allerdings fur die Tauben selbst potenziell pathogen sind. Die Verteilung der pathogenen Mikroorganismen und Parasiten zeigte signifikante Unterschiede zwischen beiden Herkunftsschlagen. Die Tauben der beiden Brutkolonien unterschieden sich in Bezug auf den Ernahrungszustand und den Befall mit zwei Federlingsarten, Columbicola columbae und Campanulotes bidentatus compar. Die Pravalenz fur Trichomonas gallinae differierte nicht signifikant zwischen Jung- und Alttauben, die Jungtauben zeigten aber...
![Research paper thumbnail of [Sociocultural reasons for the pigeon problem]](https://attachments.academia-assets.com/78106437/thumbnails/1.jpg)
](DTW. Deutsche tierarztliche Wochenschrift, 1997
The feeding of animals as a friendly gesture is deeply rooted in man. This behaviour has a negati... more The feeding of animals as a friendly gesture is deeply rooted in man. This behaviour has a negative effect on the Street-pigeons which as a consequence suffer from overpopulation. The problem can only be solved by limiting this feeding. The pigeon-feeders are the cause of the pigeon-problem in our cities. The feeders can by their motivation be classified in various groups. Play-feeders and display-feeders can be recognised. They are more easily to be dealt with than the fanatical pigeon-friends who show a strong emotional attachment to these birds. The pigeon-problem can be overcome if this stubborn group can be taught to change his behaviour. Such a solution would be highly rewarding as great sums of money are spent to remove damages caused by the pigeons to buildings and works of art.
Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)), 1998
A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the cen... more A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the centre of Basel (Altrheinweg, Klybeckquartier) is known as site for overnight accommodation and assembly of starlings (Sturnus vulgaris) during autumn. The nightly visitors cause an immense contamination that directly affects a nursery and a primary school. The aim of the present study was the evaluation of the health risk for the population due to the starlings' droppings, particularly for the children from the nursery school. Between August and December of the years 1995 and 1996 the population of starlings was observed, the contamination of the area with faeces was quantified, the presence of microorganisms in the faeces was determined and the contamination of the soil from the Altrheinweg was compared with that from other avenues and parks. Furthermore, the children attending the nursery school were monitored for possible infections due to the birds' droppings. In mid-October, w...
Pigeons chlamydiosis is a relevant public health issue and there is a need to exchange data and e... more Pigeons chlamydiosis is a relevant public health issue and there is a need to exchange data and experience about this topic among scientists of different countries. In order to address this issue, a meeting in the contex of the COST 855 Action was held in Pavia, Italy in spring 2006.
A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the cen... more A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the centre of Basel (Altrheinweg, Klybeckquartier) is known as site for overnight accommodation and assembly of starlings (Sturnus vulgaris) during autumn. The nightly visitors cause an immense contamination that directly affects a nursery and a primary school. The aim of the present study was the evaluation of the health risk for the population due to the starlings' droppings, particularly for the children from the nursery school. Between August and December of the years 1995 and 1996 the population of starlings was observed, the contamination of the area with faeces was quantified, the presence of microorganisms in the faeces was determined and the contamination of the soil from the Altrheinweg was compared with that from other avenues and parks. Furthermore, the children attending the nursery school were monitored for possible infections due to the birds' droppings. In mid - October,...
The relevance of using lucky charms in the examination room has not been well studied. In this an... more The relevance of using lucky charms in the examination room has not been well studied. In this analysis the frequency and results of using lucky charms have been determined in a group of medical students (n = 676) sitting the first examination in the medical curriculum (first propaedeutics). Approximately 10% of all candidates took lucky charms with them into the examination room. Lucky charms were worn significantly more often by female examinees than by males. However, examination results were not significantly better among charm wearers than those without. The commonest charms were in the form of ladybirds or pigs, most of the other 27 also being animal representations.
Medical and Veterinary Entomology, 2016
The medically and veterinary important feral pigeon tick Argas reflexus (Ixodida: Argasidae) Fabr... more The medically and veterinary important feral pigeon tick Argas reflexus (Ixodida: Argasidae) Fabricius usually feeds on pigeons, but if its natural hosts are not available, it also enters dwellings to bite humans that can possibly react with severe allergic reactions. Argas reflexus is ecologically extremely successful as a result of some outstanding morphological, physiological, and ethological features. Yet, it is still unknown how the pigeon tick finds its hosts. Here, different host stimuli such as living nestlings as well as begging calls, body heat, smell, host breath and tick faeces, were tested under controlled laboratory conditions. Of all stimuli tested, only heat played a role in host-finding. The heat stimulus was then tested under natural conditions within a pigeon loft. The results showed that A. reflexus is able to find a host over short distances of only a few centimetres. Furthermore, it finds its host by random movements and recognizes a host only right before direct contact is made. The findings are useful for the control of A. reflexus in infested apartments, both to diagnose an infestation and to perform a success monitoring after disinfestation.
Tierärztliche Praxis, 1994
An ethometrical analysis of street pigeons showed that most social interactions under conditions ... more An ethometrical analysis of street pigeons showed that most social interactions under conditions of overpopulation are of an aggressive nature. Through various mechanisms this frequent aggressive behaviour leads to "slumlike" living conditions characterized by intraspecific stress. It is possible to characterize street pigeons in their urban environment by calculating the frequencies of the most important aggressive and sexually-motivated social interactions. Behavioral patterns adapted to their living conditions result in misbehaviour in an anthropogenous environment. A high population density in commercial pigeon units should therefore be avoided. It is also necessary to consider the typical disposition of a race for aggressive behaviour. The frequent aggressive interactions among street pigeons at their breeding lofts seem to play an important role as a density dependent regulator of population size.
Amtstierärztl Dienst Lebensmittelkont, 2008
... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gme... more ... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gmelin 1789) in beinahe jeder Stadt zu-genommen. ... Gesundheitsgefährdungen durch die Straßentaube Columba livia: Parasiten Daniel Haag-Wackernagel ...
Annals of Applied Biology, 2005
Feral pigeons live in almost every large city in the world. The feeding of pigeons by humans, del... more Feral pigeons live in almost every large city in the world. The feeding of pigeons by humans, deliberately or accidentally, allows the build-up of large populations that can cause a variety of problems, primarily the fouling of buildings and monuments by their droppings. Excreta of wild birds are a well-known source of pathogenic microorganisms that can cause infection in man. The most important ectoparasites of feral pigeons are the red blood mite, Dermanyssus gallinae, and the pigeon tick, Argas reflexus, both of which can migrate into human living space when they lose their natural hosts. The bites of the red blood mite are irritating but harmless, whereas the pigeon tick can cause severe health problems to predisposed persons. After repeated bites from A. reflexus, people can develop IgE-mediated (type I) allergy, which in extreme situations may lead to life-threatening symptoms of anaphylactic shock. So far, one fatality due to A. reflexus deriving from feral pigeons has been reported. In the case of parasitic infestations of humans, the source must be removed by excluding pigeons from further breeding and by disinfection of the environment of pigeon-breeding sites.
SCHWEIZERISCHE MEDIZINISCHE …, 2000
... der verwendeten Glücksbringer waren Marienkäfer (Coccinella septempunctata), die sich im Chri... more ... der verwendeten Glücksbringer waren Marienkäfer (Coccinella septempunctata), die sich im Christentum schon seit Jahrhunderten grösster Beliebtheit erfreuen [6]. Im Marien-käfer ist das Rot, das Hexen und Unglück bannt, mit der heiligen Siebenzahl kombiniert [7]. Mit 12,5 ...
Ibis, 2016
Feral Pigeons Columba livia are highly adapted to urban environments and are thus often abundant ... more Feral Pigeons Columba livia are highly adapted to urban environments and are thus often abundant in cities. This can lead to various problems, including fouling of building facades and pavements, transmission of allergens and pathogenic microorganisms , and infestations of ectoparasites derived from breeding sites. To develop effective, longlasting and humane control strategies, it is necessary to understand the demography of Feral Pigeons. Although food shortage is a major source of reproductive failure in Feral Pigeons, it is still unclear at which phase of the reproductive cycle this reduces overall reproductive success. Here, we assess the effect of a sudden reduction in the food base on the reproduction of a well-studied Feral Pigeon breeding colony. The findings of this study suggest that the number of broods per pair decreases significantly during food scarcity, and that although hatching success remains constant, a significantly greater number of nestlings die during the rearing phase. This suggests that the high energy demand of Feral Pigeon nestlings could not be met under conditions of food scarcity, which reduced the total number of fledged young by more than half and led to a reduction in the colony size. These results have important implications for selecting suitable, durable and humane control strategies for the management of large Feral Pigeon populations in urban environments.
Scientific Reports, 2016
When searching for food, foraging fishes expose themselves to hidden predators. The strategies th... more When searching for food, foraging fishes expose themselves to hidden predators. The strategies that maximize the survival of foraging fishes are not well understood. Here, we describe a novel type of mobbing behaviour displayed by foraging Scolopsis affinis. The fish direct sharp water jets towards the hidden sessile annelid predator Eunice aphroditois (Bobbit worm). We recognized two different behavioural roles for mobbers (i.e., initiator and subsequent participants). The first individual to exhibit behaviour indicating the discovery of the Bobbit directed, absolutely and per time unit, more water jets than the subsequent individuals that joined the mobbing. We found evidence that the mobbing impacted the behaviour of the Bobbit, e.g., by inducing retraction. S. affinis individuals either mob alone or form mobbing groups. We speculate that this behaviour may provide social benefits for its conspecifics by securing foraging territories for S. affinis. Our results reveal a sophisticated and complex behavioural strategy to protect against a hidden predator. Mobbing in the animal kingdom is described as an approach towards a potential predator followed by swoops or runs, sometimes involving a direct attack with physical contact by the mobber 1. Mobbing is well characterized in birds, mammals, and even invertebrates 1-5. Most of the reported mobbing behaviours initiated by a prey species involve directed harassment of a mobile predator 1,3,6-9. Hidden, ambushing predators are a major threat to prey species. The timely discovery of a predator allows the danger zone to be avoided and enables countermeasures to be directed against the predator, including mobbing or even direct attacks 8. In contrast to solitary living prey, social groups can profit from warning each other of ensuing dangers. Usually, mobbing occurs as a group phenomenon, but mobbing can also be performed by a single individual 3,10,11. S. affinis is a common demersal species that lives and feeds near the seabed of the western Pacific 12. S. affinis preys on copepods, microcrustaceans, shrimps, and echinoderm larvae 12,13. Juvenile S. affinis individuals are easily recognizable by the dusky-brown mid-lateral stripe on their sides. According to our field observations we suppose that immature S. affinis individuals forage in mobile groups that are restricted to a home range. Thus, it would be highly advantageous for these individuals to know to location of a hidden predator. One such hidden ambusher of demersal species of fish is the Bobbit worm Eunice aphroditois. The Bobbit worm lives in the sedimentary beds of warmer oceans, including the Indo-Pacific and Atlantic 14. The largest specimen of a recorded Bobbit worm was 299 cm long, weighing 433 g, and it may be the longest of the polychaete worms 14. Bobbits reside in mucus-lined borrows in rocks or sediments. During the day, Bobbits are buried in the loose seabed waiting for a stimulus on one of their five antennae that protrude from the hidden burrow to lure prey fish (Fig. 1a). Armed with jaws with sharp teeth, Bobbits attack when they sense prey, grasping and dragging them down into their burrow (Fig. 1b). At night, the Bobbit changes its strategy and actively hunts by protruding from its burrow and snatching passing prey (Fig. 2 and Supplementary Movie 1). Bobbits have two eyes on the prostomium 15 and five striped antennae that exhibit wormlike movement and presumably serve to lure and detect prey. Preliminary field experiments by one of the authors showed that predation by Bobbits can be triggered only by a lure that moves like a living fish (unpublished observation by J. Lachat). Additionally, during the night, the beam of a torch can trigger an attack of the Bobbit. Therefore, Bobbits appear to detect their prey mainly by visual and tactile cues. Bobbits are known to bite humans and can cause severe wounds 16. We performed underwater field observations by attracting S. affinis as a potential prey to the location of a Bobbit to study its behaviour towards this enemy. Remarkably, we discovered that the potential prey, S. affinis,
Journal of Agricultural Science, 2012
Following the spread and increase of wild boar populations in Europe during the last decades, con... more Following the spread and increase of wild boar populations in Europe during the last decades, conflicts with humans have intensified also in Switzerland. Damage to crops and grassland augmented considerably and became unacceptable. Farmers and authorities are highly interested in efficient alternatives to the installation of costly and time consuming electric fences for crop protection. In the present study we investigated the effectiveness of a gustative repellent in field experiments with free-ranging wild boars in clover sowings, meadows, and wheat fields. Although we observed a slight trend towards a damage reduction, the results show, that the repellent was not able to prevent damage at a significant level. We further could not detect any area avoidance by the wild boars as a response to the repellent. On the basis of our findings we conclude that gustative repellents relying on learned avoidance as a consequence of negative experience are not a promising means for protection of crops and grassland from wild boar damage. We further discuss the effects of different agricultural crops and the anthropogenic influence on the frequency of damage.
... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gme... more ... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gmelin 1789) in beinahe jeder Stadt zu-genommen. ... Gesundheitsgefährdungen durch die Straßentaube Columba livia: Parasiten Daniel Haag-Wackernagel ...
Annals of agricultural and environmental medicine : AAEM, 2004
The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus c... more The report concerns a married couple who were repeatedly invaded by pigeon fleas (Ceratophyllus columbae) over a period of 2 months. The source of the fleas was a pair of breeding feral pigeons (Columba livia). The birds' nest was located in the attic immediately above the couple's apartment, and the fleas found their way along an unsealed heating pipe. The people encountered up to 40 bites per night. With invasions repeated almost every night, the man gradually developed an allergic urticarial reaction. The most traumatic experience for the couple, however, was to learn that they were invaded by fleas (initially, they had presumed they were bothered by mosquitoes). This information resulted in severe psychological distress with phobic reactions and insomnia. Despite the successful removal of the fleas and the pigeons that were source of the pest, parasitophobia of the man persisted over the following 4 months. This case is discussed from the broader aspect of health risks r...
Berliner und Munchener tierarztliche Wochenschrift, 2015
We examined 80 feral pigeons and their fecal samples from two feral pigeon lofts of the "Pig... more We examined 80 feral pigeons and their fecal samples from two feral pigeon lofts of the "Pigeon Action of Basel" (Switzerland) for different pathogens. The tested material harbored four pathogenic agents transmissible to humans (Chlamydia spp., Salmonella spec., Campylobacter jejuni, Cryptococcus neoformans) In addition several pathogens were found which are no zoonotic agents but potentially pathogenic for the pigeons themselves, such as Trichomonas gallinae, coccidia, helminths, ectoparasites and fungi. The number of pathogens and parasites detected in the fecal samples varied significantly between the two localities. The pigeons of the two investigated breeding flocks differed in nutritional status and the incidence of two species of feather lice, Columbicola columbae and Campanulotes bidentatus compar. The prevalence of Trichomonas gallinae between juveniles and adults was not significantly different but juveniles exhibited significantly heavier infestation if infected...
Es wurden 80 Strasentauben und Kotproben aus zwei Strasentaubenschlagen der „Basler Taubenaktion“... more Es wurden 80 Strasentauben und Kotproben aus zwei Strasentaubenschlagen der „Basler Taubenaktion“ (Schweiz) auf das Vorhandensein verschiedener Krankheitserreger untersucht. Dabei wurden vier auf den Menschen ubertragbare pathogene Mikroorganismen gefunden (Chlamydia spp., Salmonella spp., Campylobacter jejuni und Cryptococcus neoformans). Daruberhinaus fanden sich auch Krankheitserreger ohne zoonotisches Potential wie Trichomonas gallinae, Kokzidien, Helminthen, Ektoparasiten und Pilze, die allerdings fur die Tauben selbst potenziell pathogen sind. Die Verteilung der pathogenen Mikroorganismen und Parasiten zeigte signifikante Unterschiede zwischen beiden Herkunftsschlagen. Die Tauben der beiden Brutkolonien unterschieden sich in Bezug auf den Ernahrungszustand und den Befall mit zwei Federlingsarten, Columbicola columbae und Campanulotes bidentatus compar. Die Pravalenz fur Trichomonas gallinae differierte nicht signifikant zwischen Jung- und Alttauben, die Jungtauben zeigten aber...
DTW. Deutsche tierarztliche Wochenschrift, 1997
The feeding of animals as a friendly gesture is deeply rooted in man. This behaviour has a negati... more The feeding of animals as a friendly gesture is deeply rooted in man. This behaviour has a negative effect on the Street-pigeons which as a consequence suffer from overpopulation. The problem can only be solved by limiting this feeding. The pigeon-feeders are the cause of the pigeon-problem in our cities. The feeders can by their motivation be classified in various groups. Play-feeders and display-feeders can be recognised. They are more easily to be dealt with than the fanatical pigeon-friends who show a strong emotional attachment to these birds. The pigeon-problem can be overcome if this stubborn group can be taught to change his behaviour. Such a solution would be highly rewarding as great sums of money are spent to remove damages caused by the pigeons to buildings and works of art.
Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)), 1998
A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the cen... more A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the centre of Basel (Altrheinweg, Klybeckquartier) is known as site for overnight accommodation and assembly of starlings (Sturnus vulgaris) during autumn. The nightly visitors cause an immense contamination that directly affects a nursery and a primary school. The aim of the present study was the evaluation of the health risk for the population due to the starlings' droppings, particularly for the children from the nursery school. Between August and December of the years 1995 and 1996 the population of starlings was observed, the contamination of the area with faeces was quantified, the presence of microorganisms in the faeces was determined and the contamination of the soil from the Altrheinweg was compared with that from other avenues and parks. Furthermore, the children attending the nursery school were monitored for possible infections due to the birds' droppings. In mid-October, w...
Pigeons chlamydiosis is a relevant public health issue and there is a need to exchange data and e... more Pigeons chlamydiosis is a relevant public health issue and there is a need to exchange data and experience about this topic among scientists of different countries. In order to address this issue, a meeting in the contex of the COST 855 Action was held in Pavia, Italy in spring 2006.
A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the cen... more A Natural Phenomenon, Molestation or a Health Risk? For the last two decades an avenue in the centre of Basel (Altrheinweg, Klybeckquartier) is known as site for overnight accommodation and assembly of starlings (Sturnus vulgaris) during autumn. The nightly visitors cause an immense contamination that directly affects a nursery and a primary school. The aim of the present study was the evaluation of the health risk for the population due to the starlings' droppings, particularly for the children from the nursery school. Between August and December of the years 1995 and 1996 the population of starlings was observed, the contamination of the area with faeces was quantified, the presence of microorganisms in the faeces was determined and the contamination of the soil from the Altrheinweg was compared with that from other avenues and parks. Furthermore, the children attending the nursery school were monitored for possible infections due to the birds' droppings. In mid - October,...
The relevance of using lucky charms in the examination room has not been well studied. In this an... more The relevance of using lucky charms in the examination room has not been well studied. In this analysis the frequency and results of using lucky charms have been determined in a group of medical students (n = 676) sitting the first examination in the medical curriculum (first propaedeutics). Approximately 10% of all candidates took lucky charms with them into the examination room. Lucky charms were worn significantly more often by female examinees than by males. However, examination results were not significantly better among charm wearers than those without. The commonest charms were in the form of ladybirds or pigs, most of the other 27 also being animal representations.
Medical and Veterinary Entomology, 2016
The medically and veterinary important feral pigeon tick Argas reflexus (Ixodida: Argasidae) Fabr... more The medically and veterinary important feral pigeon tick Argas reflexus (Ixodida: Argasidae) Fabricius usually feeds on pigeons, but if its natural hosts are not available, it also enters dwellings to bite humans that can possibly react with severe allergic reactions. Argas reflexus is ecologically extremely successful as a result of some outstanding morphological, physiological, and ethological features. Yet, it is still unknown how the pigeon tick finds its hosts. Here, different host stimuli such as living nestlings as well as begging calls, body heat, smell, host breath and tick faeces, were tested under controlled laboratory conditions. Of all stimuli tested, only heat played a role in host-finding. The heat stimulus was then tested under natural conditions within a pigeon loft. The results showed that A. reflexus is able to find a host over short distances of only a few centimetres. Furthermore, it finds its host by random movements and recognizes a host only right before direct contact is made. The findings are useful for the control of A. reflexus in infested apartments, both to diagnose an infestation and to perform a success monitoring after disinfestation.
Tierärztliche Praxis, 1994
An ethometrical analysis of street pigeons showed that most social interactions under conditions ... more An ethometrical analysis of street pigeons showed that most social interactions under conditions of overpopulation are of an aggressive nature. Through various mechanisms this frequent aggressive behaviour leads to "slumlike" living conditions characterized by intraspecific stress. It is possible to characterize street pigeons in their urban environment by calculating the frequencies of the most important aggressive and sexually-motivated social interactions. Behavioral patterns adapted to their living conditions result in misbehaviour in an anthropogenous environment. A high population density in commercial pigeon units should therefore be avoided. It is also necessary to consider the typical disposition of a race for aggressive behaviour. The frequent aggressive interactions among street pigeons at their breeding lofts seem to play an important role as a density dependent regulator of population size.
Amtstierärztl Dienst Lebensmittelkont, 2008
... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gme... more ... Einleitung In den letzten Jahrzehnten haben die Be-stände der Straßentaube Columba livia (Gmelin 1789) in beinahe jeder Stadt zu-genommen. ... Gesundheitsgefährdungen durch die Straßentaube Columba livia: Parasiten Daniel Haag-Wackernagel ...
Annals of Applied Biology, 2005
Feral pigeons live in almost every large city in the world. The feeding of pigeons by humans, del... more Feral pigeons live in almost every large city in the world. The feeding of pigeons by humans, deliberately or accidentally, allows the build-up of large populations that can cause a variety of problems, primarily the fouling of buildings and monuments by their droppings. Excreta of wild birds are a well-known source of pathogenic microorganisms that can cause infection in man. The most important ectoparasites of feral pigeons are the red blood mite, Dermanyssus gallinae, and the pigeon tick, Argas reflexus, both of which can migrate into human living space when they lose their natural hosts. The bites of the red blood mite are irritating but harmless, whereas the pigeon tick can cause severe health problems to predisposed persons. After repeated bites from A. reflexus, people can develop IgE-mediated (type I) allergy, which in extreme situations may lead to life-threatening symptoms of anaphylactic shock. So far, one fatality due to A. reflexus deriving from feral pigeons has been reported. In the case of parasitic infestations of humans, the source must be removed by excluding pigeons from further breeding and by disinfection of the environment of pigeon-breeding sites.
SCHWEIZERISCHE MEDIZINISCHE …, 2000
... der verwendeten Glücksbringer waren Marienkäfer (Coccinella septempunctata), die sich im Chri... more ... der verwendeten Glücksbringer waren Marienkäfer (Coccinella septempunctata), die sich im Christentum schon seit Jahrhunderten grösster Beliebtheit erfreuen [6]. Im Marien-käfer ist das Rot, das Hexen und Unglück bannt, mit der heiligen Siebenzahl kombiniert [7]. Mit 12,5 ...
Ibis, 2016
Feral Pigeons Columba livia are highly adapted to urban environments and are thus often abundant ... more Feral Pigeons Columba livia are highly adapted to urban environments and are thus often abundant in cities. This can lead to various problems, including fouling of building facades and pavements, transmission of allergens and pathogenic microorganisms , and infestations of ectoparasites derived from breeding sites. To develop effective, longlasting and humane control strategies, it is necessary to understand the demography of Feral Pigeons. Although food shortage is a major source of reproductive failure in Feral Pigeons, it is still unclear at which phase of the reproductive cycle this reduces overall reproductive success. Here, we assess the effect of a sudden reduction in the food base on the reproduction of a well-studied Feral Pigeon breeding colony. The findings of this study suggest that the number of broods per pair decreases significantly during food scarcity, and that although hatching success remains constant, a significantly greater number of nestlings die during the rearing phase. This suggests that the high energy demand of Feral Pigeon nestlings could not be met under conditions of food scarcity, which reduced the total number of fledged young by more than half and led to a reduction in the colony size. These results have important implications for selecting suitable, durable and humane control strategies for the management of large Feral Pigeon populations in urban environments.
Scientific Reports, 2016
When searching for food, foraging fishes expose themselves to hidden predators. The strategies th... more When searching for food, foraging fishes expose themselves to hidden predators. The strategies that maximize the survival of foraging fishes are not well understood. Here, we describe a novel type of mobbing behaviour displayed by foraging Scolopsis affinis. The fish direct sharp water jets towards the hidden sessile annelid predator Eunice aphroditois (Bobbit worm). We recognized two different behavioural roles for mobbers (i.e., initiator and subsequent participants). The first individual to exhibit behaviour indicating the discovery of the Bobbit directed, absolutely and per time unit, more water jets than the subsequent individuals that joined the mobbing. We found evidence that the mobbing impacted the behaviour of the Bobbit, e.g., by inducing retraction. S. affinis individuals either mob alone or form mobbing groups. We speculate that this behaviour may provide social benefits for its conspecifics by securing foraging territories for S. affinis. Our results reveal a sophisticated and complex behavioural strategy to protect against a hidden predator. Mobbing in the animal kingdom is described as an approach towards a potential predator followed by swoops or runs, sometimes involving a direct attack with physical contact by the mobber 1. Mobbing is well characterized in birds, mammals, and even invertebrates 1-5. Most of the reported mobbing behaviours initiated by a prey species involve directed harassment of a mobile predator 1,3,6-9. Hidden, ambushing predators are a major threat to prey species. The timely discovery of a predator allows the danger zone to be avoided and enables countermeasures to be directed against the predator, including mobbing or even direct attacks 8. In contrast to solitary living prey, social groups can profit from warning each other of ensuing dangers. Usually, mobbing occurs as a group phenomenon, but mobbing can also be performed by a single individual 3,10,11. S. affinis is a common demersal species that lives and feeds near the seabed of the western Pacific 12. S. affinis preys on copepods, microcrustaceans, shrimps, and echinoderm larvae 12,13. Juvenile S. affinis individuals are easily recognizable by the dusky-brown mid-lateral stripe on their sides. According to our field observations we suppose that immature S. affinis individuals forage in mobile groups that are restricted to a home range. Thus, it would be highly advantageous for these individuals to know to location of a hidden predator. One such hidden ambusher of demersal species of fish is the Bobbit worm Eunice aphroditois. The Bobbit worm lives in the sedimentary beds of warmer oceans, including the Indo-Pacific and Atlantic 14. The largest specimen of a recorded Bobbit worm was 299 cm long, weighing 433 g, and it may be the longest of the polychaete worms 14. Bobbits reside in mucus-lined borrows in rocks or sediments. During the day, Bobbits are buried in the loose seabed waiting for a stimulus on one of their five antennae that protrude from the hidden burrow to lure prey fish (Fig. 1a). Armed with jaws with sharp teeth, Bobbits attack when they sense prey, grasping and dragging them down into their burrow (Fig. 1b). At night, the Bobbit changes its strategy and actively hunts by protruding from its burrow and snatching passing prey (Fig. 2 and Supplementary Movie 1). Bobbits have two eyes on the prostomium 15 and five striped antennae that exhibit wormlike movement and presumably serve to lure and detect prey. Preliminary field experiments by one of the authors showed that predation by Bobbits can be triggered only by a lure that moves like a living fish (unpublished observation by J. Lachat). Additionally, during the night, the beam of a torch can trigger an attack of the Bobbit. Therefore, Bobbits appear to detect their prey mainly by visual and tactile cues. Bobbits are known to bite humans and can cause severe wounds 16. We performed underwater field observations by attracting S. affinis as a potential prey to the location of a Bobbit to study its behaviour towards this enemy. Remarkably, we discovered that the potential prey, S. affinis,
Journal of Agricultural Science, 2012
Following the spread and increase of wild boar populations in Europe during the last decades, con... more Following the spread and increase of wild boar populations in Europe during the last decades, conflicts with humans have intensified also in Switzerland. Damage to crops and grassland augmented considerably and became unacceptable. Farmers and authorities are highly interested in efficient alternatives to the installation of costly and time consuming electric fences for crop protection. In the present study we investigated the effectiveness of a gustative repellent in field experiments with free-ranging wild boars in clover sowings, meadows, and wheat fields. Although we observed a slight trend towards a damage reduction, the results show, that the repellent was not able to prevent damage at a significant level. We further could not detect any area avoidance by the wild boars as a response to the repellent. On the basis of our findings we conclude that gustative repellents relying on learned avoidance as a consequence of negative experience are not a promising means for protection of crops and grassland from wild boar damage. We further discuss the effects of different agricultural crops and the anthropogenic influence on the frequency of damage.