Strophe Length in Spontaneous Songs Predicts Male Response to Playback in the Hoopoe Upupa epops

Hoopoe (Upupa epops, Coraciformes) males produce a very simple song during the breeding season in order to attract females and repel intruders. Strophes vary in length (i.e. number of elements) both within and between males, and previous studies have shown that this song cue is positively correlated with male condition and breeding success. In the present study we tested whether strophe length of males influences male behaviour during intra‐sexual contests, in a colour‐ringed population in southeast Spain. Paired males were presented with a recorded song with long strophes during the pre‐laying period, while they were near their mates, in order to provoke male mate‐defence behaviour. Most males responded to the playback, but the strategy of defence adopted depended on their own strophe length in spontaneous songs recorded before the experiments. While singing responses were common to most of the males, only those using long strophes adopted the most risky strategy of approaching the loudspeaker. However, the males that approached produced abnormal songs during playback, that were shorter and with fewer strophes than those of males that did not approach, and used shorter strophes in comparison with spontaneous songs before the experiment. These differences in quality of the song produced in response to the playback suggest that long‐strophe males were basing their response mainly on attacking rather than singing, while short‐strophe males tried to resolve the contest at a distance by means of their song. These results show that strophe length reflects some component of the competitive ability of males (either physical strength or aggressiveness) in the hoopoe, which together with previous results regarding its role for female choice, show that it is a sexual signal with dual function.     

Characterization of Antimicrobial Substances Produced by Enterococcus faecalis MRR 10-3, Isolated from the Uropygial Gland of the Hoopoe (Upupa epops)

The uropygial gland (preen gland) is a holocrine secretory gland situated at the base of the tail in birds which produces a hydrophobic fatty secretion. In certain birds, such as the hoopoe, Upupa epops, the composition of this secretion is influenced by both seasonal and sexual factors, becoming darker and more malodorous in females and in their nestlings during the nesting phase. The secretion is spread throughout the plumage when the bird preens itself, leaving its feathers flexible and waterproof. It is also thought to play a role in defending the bird against predators and parasites. We have isolated from the uropygial secretion of a nestling a bacterium that grows in monospecific culture which we have identified unambiguously by phenotypic and genotypic means as Enterococcus faecalis. The strain in question produces antibacterial substances that are active against all gram-positive bacteria assayed and also against some gram-negative strains. Its peptide nature identifies it as a bacteriocin within the group known as enterocins. Two peptides were purified to homogeneity (MR10A and MR10B), and matrix-assisted laser desorption ionization-time of flight (mass spectrometry) analysis showed masses of 5201.58 and 5207.7 Da, respectively. Amino acid sequencing of both peptides revealed high similarity with enterocin L50A and L50B (L. M. Cintas, P. Casaus, H. Holo, P. E. Hernández, I. F. Nes, and L. S. Håvarstein, J. Bacteriol. 180:1988-1994, 1998). PCR amplification of total DNA from strain MRR10-3 with primers for the L50A/B structural genes and sequencing of the amplified fragment revealed almost identical sequences, except for a single conservative change in residue 38 (Glu→Asp) in MR10A and two changes in residues 9 (Thr→Ala) and 15 (Leu→Phe) in MR10B. This is the first time that the production of bacteriocins by a bacterium isolated from the uropygial gland has been described. The production of these broad-spectrum antibacterial substances by an enterococcal strain living in the uropygial gland may be important to the hygiene of the nest and thus to the health of the eggs and chicks.     

戴胜的一些生态资料

报告1997-2002年的3～10月,在历山国家级自然保护区搜集到的戴胜的一些生态资料。戴胜每年3月上旬迁来历山保护区,9月底陆续迁离,居留期202-205天。在历山保护区每公里遇见率繁殖后比繁殖前增长96．55％。每年繁殖一次。窝卵数5～7枚,孵化期18天,巢内育雏期18天,巢外育幼期10～18天。     

Attraction of Hoopoe Upupa epops females and males by means of song playback in the field: influence of strophe length

Experimental Hoopoe Upupa epops songs prepared with synthetic sound to differ in strophe length were used to test whether Hoopoe females prefer long strophes. The songs were broadcast simultaneously in the field from two loudspeakers situated 100 m apart, in early spring, when females actively search for mates. The playbacks attracted a total of 87 individuals, both males and females, with a maximum of five individuals (three males and two females) per trial. A female was considered to have been attracted by the song broadcast from a loudspeaker when she approached unaccompanied by a male, and when there was no male nearby. A total of 15 females chose one of the songs and significantly more were attracted by the one with long strophes. These results suggest that in the Hoopoe, male song attracts females, and that strophe length is a sexually selected song cue. There were no differences in the number or kind of males (classified according to strophe length) attracted by each playback. Frequently the experiment attracted more than one male simultaneously. These aggregations cannot be explained as territorial responses, and their significance is discussed together with that of natural spontaneous groupings of displaying males. Apparently males aggregate where they expect to find females.     

Food provision to nestlings in the Hoopoe Upupa epops: implications for the conservation of a small endangered population in the Swiss Alps

In an attempt to recognize the possible ecological causes of the decline of a population of Hoopoes Upupa epops in the Swiss Alps, we collected data on resource exploitation. The prey provisioned to nestlings by parents was investigated at four breeding sites using photographs (n = 4353, 80% of which enabled prey identification). Molecrickets Gryllotalpa gryllotalpa and Lepidoptera (larvae and pupae) were dominant in nestling diet (93% frequency; 97% biomass). Although Molecrickets were provisioned less frequently (26%) than Lepidoptera (67%), they represented 68% of the total biomass (vs 29% for Lepidoptera). There was an overall negative relationship between the proportion of Molecricket biomass in the diet and the parents' feeding rate, whereas a comparison between broods showed that a higher provisioning activity did not lead to an increase in the biomass supplied to the chicks. A diet based on Molecrickets therefore appears to be energetically advantageous. As Molecrickets are a traditional prey of Hoopoes in central Europe, this might be relevant to other populations. In the study area, Molecrickets occur only on the intensively cultivated plain, whereas the majority of Hoopoe pairs nest at various altitudes on the foothills adjacent to the plain as the latter provides at present almost no suitable nesting sites. Hoopoes breeding higher up on the foothills seem to experience greater provisioning costs and have, on average, lower breeding success. Providing nest sites on the plain is the main conservation measure proposed for the local Hoopoe population. Further attention should also be paid to Molecrickets as these may be crucial for Hoopoes.     

Arthropods (Acarina, Coleoptera, Siphonaptera) in nests of hoopoe (Upupa epops) in Central Europe

In 1993–1995 and 2009–2011, during investigation of reproduction biology of hoopoe, 63 nests of this species were collected after fledging of the chicks in Slovakia and Austria and their arthropod fauna was analyzed. Altogether 5,481 individuals and 34 species of mesostigmatic mites were found in 82.5% of the nests examined. The nidicolous mite Androlaelaps casalis was most abundant and frequent, representing 91.7% of all individuals. The richest in species were saprophilous mites (64.7% of all recorded species), while ectoparasites of the genera Dermanyssus and Ornithonyssus represented only 0.4% of all mites. Only 8 beetle species represented by 65 individuals were found in 18 nests. The dominant trophical group were carnivores (mainly nidicolous Gnathoncus buyssoni) with almost identical representation in (86.2%), followed by a similar representation of necrophags (10.8%). Unlike nests of other birds, the typical nidicolous species Haploglossa puncticollis and the fungivors were absent due to the dry character of studied countryside and placement of the nests in boxes situated in vineyard cottages. Only one species of fleas, Ceratophyllus gallinae — parasitizing first of all in the passeriform birds and being particularly abundant in the cavity nesting birds was recorded in hoopoe nests.     

Predation by the hoopoe (Upupa epops) on pupae of Thaumetopoea pityocampa and the likelyinfluence on other natural enemies

The hoopoe (Upupa epops L.) is an insectivorousbird often preying on larvae and pupae of the pineprocessionary caterpillar (Thaumetopoeapityocampa Denis & Schiffermüller), the mostimportant defoliator of pines in Southern Europe andNorthern Africa. The first half of the breeding seasonof this migratory bird coincides with the pupal stageof the insect. Bird predation of pupae was quantifiedin two years in a Pinus nigra stand of northernItaly by periodic counting of the empty cocoons lefton the soil surface after extraction. The predationrate, estimated on 20 pupation sites representing thewhole stand, was 74.1% in 1993 and 68.3% in 1994.Predation was higher in the upper part of the soil andthen progressively decreased with increasing depth.The hoopoe may also prey on cocoons containing pupaeinfected by pathogenic fungi or parasitoids. Anexclosure experiment showed that the bird mayinterfere with these other mortality factors. Threepupal parasitoids, the ichneumonids Erigorgusfemorator Aubert and Coelichneumon rudis (Boyerde Fonscolombe) and the pteromalid Conomoriumpityocampae Graham, were significantly less frequentin the exposed sites. The fungus Beauveriabassiana (Balsamo) Vuillemin and the most abundantpupal parasitoid, Villa brunnea Becker (Diptera:Bombyliidae), caused the highest pupal mortality atboth protected and exposed sites. The bird seems to bean incompletely additive mortality factor acting onthe pest and it can also alter the relativemortalities imposed by the other natural enemies.     

Characterization of antimicrobial substances produced by Enterococcus faecalis MRR 10-3, isolated from the uropygial gland of the hoopoe (Upupa epops)

The uropygial gland (preen gland) is a holocrine secretory gland situated at the base of the tail in birds which produces a hydrophobic fatty secretion. In certain birds, such as the hoopoe, Upupa epops, the composition of this secretion is influenced by both seasonal and sexual factors, becoming darker and more malodorous in females and in their nestlings during the nesting phase. The secretion is spread throughout the plumage when the bird preens itself, leaving its feathers flexible and waterproof. It is also thought to play a role in defending the bird against predators and parasites. We have isolated from the uropygial secretion of a nestling a bacterium that grows in monospecific culture which we have identified unambiguously by phenotypic and genotypic means as Enterococcus faecalis. The strain in question produces antibacterial substances that are active against all gram-positive bacteria assayed and also against some gram-negative strains. Its peptide nature identifies it as a bacteriocin within the group known as enterocins. Two peptides were purified to homogeneity (MR10A and MR10B), and matrix-assisted laser desorption ionization-time of flight (mass spectrometry) analysis showed masses of 5201.58 and 5207.7 Da, respectively. Amino acid sequencing of both peptides revealed high similarity with enterocin L50A and L50B (L. M. Cintas, P. Casaus, H. Holo, P. E. Hernández, I. F. Nes, and L. S. H?varstein, J. Bacteriol. 180:1988-1994, 1998). PCR amplification of total DNA from strain MRR10-3 with primers for the L50A/B structural genes and sequencing of the amplified fragment revealed almost identical sequences, except for a single conservative change in residue 38 (Glu-->Asp) in MR10A and two changes in residues 9 (Thr-->Ala) and 15 (Leu-->Phe) in MR10B. This is the first time that the production of bacteriocins by a bacterium isolated from the uropygial gland has been described. The production of these broad-spectrum antibacterial substances by an enterococcal strain living in the uropygial gland may be important to the hygiene of the nest and thus to the health of the eggs and chicks.     

Dati Cariologici Sull'Arisarum Proboscideum (L.) Savi. II

Abstract

Caryological data on «Arisarum proboscideum» (L.) Savi. II. – In specimens of «Arisarum proboscideum» (L.) Savi collected near Acerno (Salerno) two different chromosome numbers – 2n = 28 and 2n = 42 – have been found. In two localities of Tuscany (Consuma, in the upper Valdarno, and San-sepolcro, near Arezzo) only the number 2n = 28 has been found, as it was already reported for Reggello (FABBRI 1966a). Moreover, in regard to the number of female flowers present in each spadix, a greater variability has been observed in the Acerno and Avellino populations (1 – 6 fem. flowers; see FABBRI 1966b) than in the Tuscan ones (1 – 3 fem. flowers); this difference in variability could be possibly connected with the different caryological situation.     

Mitochondria. II. The nuclear-mitochondrial relationship in Pelomyxa carolinensis Wilson (Chaos chaos L.)

This study has demonstrated that in the ameba, Pelomyxa carolinensis Wilson (Chaos chaos L.) the limiting membranes of mitochondria and postdivision nuclei are often continuous. The morphological relationship may be functional in that it permits an exchange of material resulting directly or indirectly in an increased enzyme content of the mitochondria. It is suggested that through a series of progressive foldings of its envelope, the nucleus may be a site of formation of mitochondria.     

The control of the proventriculus in the honeybee (Apis mellifera carnica L.) II. Feedback mechanisms

The mechanisms underlying the control of solution transport rates through the proventriculus in foraging honeybees were investigated in individuals trained to collect defined amounts of sugar solutions. Following feeding, bees were injected either with metabolisable (glucose, fructose, trehalose), or non-metabolisable (sorbose) sugars, in order to distinguish between haemolymph osmolarity and haemolymph sugar levels as factors controlling the solution transport rates through the proventriculus. After a fixed period, workers were dissected in order to measure crop content and haemolymph sugar titers. Between feeding and dissection, the metabolic rate of every investigated forager was measured using open-flow respirometry. Bees injected with metabolisable sugars 15 min after feeding were observed to reduce their solution transport rates through the proventriculus, but injection of non-metabolisable sugars had no influence on them. This suggests that the solution transport rate through the proventriculus is controlled by the concentration of metabolisable compounds in the haemolymph, and not by the haemolymph osmolarity. A period of 10 min after injection of metabolisable sugars was enough to observe reduced solution transport rates. However, if bees were injected only 5 min after feeding, no reduced solution transport rates were observed 10 min after injection.     

Relative importance of factors affecting nestling immune response differs between junior and senior nestlings within broods of hoopoes Upupa epops

Animals should invest in the immune system to protect themselves from parasites, but the cost of immune responses may limit investment depending on resource availability. In birds' broods, senior and junior chicks in size hierarchies face different rearing conditions, and thus we predicted that factors affecting immune response should differ between them. In asynchronously hatched hoopoe Upupa epops broods, we found that the immune response of senior nestlings was not related to their body condition, but positively related to risk of parasitism (which was indirectly estimated by laying date). This suggests that their immunocompetence is not limited by access to resources, and they can differentially invest in immune response with increasing risk of parasitism. On the other hand, immune response of junior nestlings was related to their body condition, but secondarily also to risk of parasitism. Our results agree with previous studies that have found significant influence of nutritional status and risk of parasitism on nestlings immune defence, but show that the effects of these environmental factors on nestling immunocompetence differ between nestlings occupying high and low rank positions in size hierarchies. The possible influence of maternal effects on the results found is also discussed.     

Comparative ecology of Gammarus pulex (L.) and Asellus aquaticus (L.) II: fungal preferences

This paper continues to explore niche differentiation in Gammarus pulex and Asellus aquaticus by analysis of their food preferences. Individuals from both species discriminated between leaf discs colonized by different fungal species and exhibited strong preferences for Anguillospora longissima and Heliscus lugdunensis. Fungal preferences were not correlated with the relative abundance of fungi in the field and there was considerable intra-population variability in food preferences — both between individuals and for the same individual through time. Niche overlap between animals from all four study populations was high and there was no evidence of differences in the potential trophic niches of animals from sympatric and allopatric populations.     

Mitochondria : II. The Nuclear-Mitochondrial Relationship in Pelomyxa carolinensis Wilson (Chaos chaos L.)

This study has demonstrated that in the ameba, Pelomyxa carolinensis Wilson (Chaos chaos L.) the limiting membranes of mitochondria and postdivision nuclei are often continuous. The morphological relationship may be functional in that it permits an exchange of material resulting directly or indirectly in an increased enzyme content of the mitochondria. It is suggested that through a series of progressive foldings of its envelope, the nucleus may be a site of formation of mitochondria.     

The Distribution of Silicon Deposits in the Roots of Molinia caerulea (L.) Moench. and Sorghum bicolor (L.) Moench.

The occurrence of silica in relation to meristematic zones andthe thickening of the endodermis in the roots of Molinia caerulea(L.) Moench. and Sorghum bicolor (L.) Moench. has been investigatedby means of the electron-probe microanalyser and the scanningelectron microscope. In proximal regions of mature roots ofM. caerulea, the central strengthening tissue of the stele,the vessel walls, the endodermis and the sub-epidermal sclerenchymaare areas of heavy accumulation. The distal regions of suchroots are relatively free of silicon and show little thickeningof the inner tangential walls of the endodermis or of the cellsof the strengthening tissues. The thickening of these elementsis shown to be associated with their location and the age ofthe root. In the proximal regions of S. bicolor, silicon is detected andlargely confined to the inner tangential walls of the endodermiswhich display some thickening. In addition, discrete and evenly-distributeddeposits varying in size partly fill the lumen of this layer.Some cells exhibit a number of smaller protrusions. High magnificationsof these lumen deposits show a distinct granular structure incontrast to the very uniform pattern of the wall deposits. The results are compared with deposits in grass leaves and inflorescencebracts and in woody perennials. The presence of silicon in additionto suberin, lignin and polyphenols in the thickened endodermalwall is also discussed in relation to the recognized functionof the endodermis.     

The cuticle of the crabs Cancer pagurus L. and Carcinus maenas (L.)

Fine closely-packed parallel fibres pass obliquely, at an angle of about 10° to the horizontal, through the cuticles of Cancer and Carcinus . They lie on axes parallel to the four faces of an obtuse pyramid, and have no counterpart in the model proposed by Bouligand (1965, 1971, 1972).
Replication of vertically broken surfaces of cuticle on cellulose acetate film shows that the laminae of the cuticle are discrete structural entities which preserve their identity around the angle formed by two vertical faces meeting at right-angles. This does not conform to the requirements of the Bouligand model.