Spawning behavior of the pygmy leatherjacket Brachaluteres jacksonianus (Monacanthidae) in southeastern Australia

Spawning behavior of the pygmy leatherjacket Brachaluteres jacksonianus was studied in southeastern Australia. Prespawning females thrust the snout repeatedly into spawning substrata, while males exhibited courtship display and nuzzled the female’s face. The females and males touched their abdomens in pairs and released gametes. No parental egg care was observed after spawning. Fertilized eggs measured 0.74 mm in diameter, and each clutch contained 50–191 eggs. The eggs were attached to filamentous red algae, which were found on the surface of the seagrass and other substrata. Reproductive ecology of B. jacksonianus is similar to that of congeneric Brachaluteres ulvarum, although selection of spawning substrata differed in two species.Supplementary material to this paper is available in electronic format at http://dx.doi.org/10.1007/s10228-005-0272-8     

The membranous labyrinth and its innervation inChaetodon trifasciatus (Pisces,Teleostei, Chaetodontidae)

Synopsis In the butterflyfishChaetodon trifasciatus, the labyrinth is characterized by its elevated form and especially the size of the vertical canals, the almost circular form of the horizontal canal and its posterior opening not directly in the utriculus but in the common pillar of the two vertical canals. There is an almost complete separation between utriculus and sacculus which are only linked by a virtual pore. The lagena, which is medially situated to the posterior part of the sacculus, is separated from it by an incomplete vertical wall. There are two maculae neglectae, the anterior macula being situated in the pore separating utriculus from sacculus and filling this pore, the posterior in a gutter of the floor of the utriculus. A long and narrow endolymphatic canal, originating from the sacculus close to the communication with the utriculus, follows the common pillar of the two vertical canals and widens into an endolymphatic sac at the top of the membranous labyrinth. The innervation of the labyrinth is made by the acoustic ganglion, which is connected to the brain by two roots and elongated into three parts: the anterior part innervates the anterior and horizontal cristae and the utricular and saccular maculae; the middle part innervates the macula sacculae and the macula neglecta 1; the posterior part innervates the macula neglecta II, the macula lagenae and the posterior crista. The important size of the vertical canals and the almost circular form of the horizontal canal may reflect very precise locomotory aptitudes.     

Spawning and nesting behavior of the waccamaw darter,Etheostoma perlongum

Synopsis The spawning and nesting behavior ofEtheostoma (Boleosoma) perlongum was investigated in the field and laboratory. Sexual dimorphism is highly developed in such features as genital papillae, first dorsal and paired fins, and nuptial coloration. A reproductive migration from mid-lake to shore occurs in the spring: males precede females to select nest sites under submerged sticks and other debris. The male excavates a depression beneath the submerged object. Gonad analysis indicates a single spawning season extending from March through June. Nests were found from late April to mid-June and were guarded by a single male for periods of 13 to 36 days. Males initiate courtship by lateral display, lead the female to the nest site and show the nest by inverting. The female responds by tail up, tail wag and circle; males also tail wag and circle. Spawning pairs invert, usually in unison, and orient head to head or, less often, head to tail. The female deposits eggs while holding her body in a weak S or J shape with the caudal peduncle held away from the spawning substrate while vibrating.     

Sound production and associated behavior in a cichlid fish,Cichlasoma centrarchus. II. Breeding pairs

Synopsis Pairs of Cichlasoma centrarchus were observed daily in the laboratory. Both males and females made sounds during a breeding cycle but all sounds were aggressive in context; no sounds were heard to accompany courtship. Males made more sounds before spawning than afterwards and these were associated with territorial defense and with establishment of dominance over the female. Females produced more sounds after spawning than before, most in the context of brood defense but some toward the male during pre-spawning nest preparation. Prior to spawning, the number of sounds made by the males toward their mates increased but the aggressive actions accompanying them became less intense. No such inverse correlation of agonistic intensity with number of sounds made was found for the females. From this study and earlier ones by the author it was concluded that sound in this species is a threat display which 1) provides an expression for agonism alternative to the performance of actions which could injure the female or drive her away, and 2) lessens the risk of injury to male or female during territory or brood defense.     

Pair behavior and spacing in butterflyfishes (Chaetodontidae)

Synopsis Three species of butterflyfishes, Chaetodon multicinctus, C. quadrimaculatus and C. ornatissimus were observed over a seven month period on the Kona coast of the island of Hawaii. All three species were found to be exclusively paired. However, C. quadrimaculatus and C. ornatissimus pair mates spent less time together and had longer separations and fewer meetings than did C. multicinctus pairs. All three species occupied and defended intraspecifically exclusive territories. Territories were maintained through mutual avoidance with occasional agonistic interactions.     

Spawning behavior of snubnose darters (Percidae) in natural and laboratory environments

Eight species of snubnose darters (genus Etheostoma) were observed and filmed to compare the spawning behavior in the field and in aquaria. These darters exhibited substrate searching, male lateral quivers, and head jabbing behavior in both the field and aquaria. In streams, snubnose darters attached eggs singly to cobble and larger rock substrates, while in aquaria several species were found to attach eggs to fine aquarium gravel as well as cobble and larger rocks. In general, these results support previous aquarium studies of snubnose darters. Information on spawning behavior in snubnose darters as well as darters of the closely related subgenus Etheostoma is synthesized in order to address the phylogenetic affinities of some species in this group of fish.     

Variation of territory size and defense behavior in breeding pairs of the endemic Lake Tanganyika cichlid fish Variabilichromis moorii

Lake Tanganyika harbors the ecologically, morphologically, and behaviorally most diverse species flock of cichlid fishes. It is comprised by substrate breeding and mouthbrooding species, most of which live in littoral habitats. Species communities are characterized by complex behavioral and trophic interactions, resulting in a dense pattern of partially overlapping territories, depending on the degree of ecological distinctness. We studied territorial behavior of breeding pairs in a substrate breeding species, with respect to territory size and defense behavior. The study species Variabilichromis moorii belongs to the tribe Lamprologini, the most species rich tribe of cichlids in Lake Tanganyika. Our study shows that breeding pairs of V. moorii can have highly complex territories, in which both parents hold separate sub-territories which are shifted slightly according to the movements of the fry, but the outer borders are conjointly defended. The size of the total defended territory varied from <1 to almost 4 m², averaging at about 2 m². Depending on presence of competitors or fry-predators evoking agonistic interactions, the territory size varied quite substantially over the day. Attack rates and size of the defended area decreased with water depth. Agonistic behavior was observed toward heterospecifics as well as conspecifics, with heterospecific attacks mostly concerning territorial neighbors and potential fry-predators in about equal frequencies. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Guest editors: T. Wilke, R. V?in?l? & F. Riedel Patterns and Processes of Speciation in Ancient Lakes: Proceedings of the Fourth Symposium on Speciation in Ancient Lakes, Berlin, Germany, September 4–8, 2006     

Spawning behavior of Arctic charr (Salvelinus alpinus): Spawning synchrony,vibrational communication,and mate guarding

A mismatch in synchrony between male and female gamete release in external fertilizers can result in reduced or failed fertilization, sperm competition, and reduced paternity. In Arctic charr (Salvelinus alpinus), males can adopt either a guard or sneak tactic resulting in both pre‐ and postcopulatory competition between males with alternative reproduction tactics. Here, spawning behavior of free‐living Arctic charr was video‐recorded, and their reproductive behavior was analyzed. From evaluating 157 spawning events, we observed that females mainly spawned with a guarding male and that the female and the guarding male synchronized timing of gamete release under sperm competition. Although sneakers spawned with higher synchrony than the guarding male in single‐male spawning events, the average sneaker released his milt less synchronized with the female than the guarding male under sperm competition. Approximately 50% of the recorded spawning events occurred under sperm competition, where each event included an average of 2.7 males. Additionally, sneakers were more exposed to sperm competition than guarding males. An influx of males, in close proximity to the female, occurred during the behavioral sequences leading up to egg release, but this influx seemed not dependent on egg release, suggesting that something else than gonadal product attracts sneaker males to the spawning female. Just before and during the actual release of gametes, the spawning couple vibrates their bodies in close contact and it seems likely that this vibrational communication between the spawning couple, which results in a larger amplitude sound wave than seen under regular courting, reveals time of gamete release to sneaker males. Thus, vibrational communication may enable synchrony between the guarding male and the female, and this might be traded against the cost of higher detectability from surrounding sneaker males, eavesdropping in close proximity.     

Larval biology of butterflyfishes (Pisces,Chaetodontidae): what do we really know?

Synopsis Relatively little is known of the pelagic portion of the life history of butterflyfishes. Eggs are small (<1 mm), pelagic and hatch in less than 30 hours. Most species pass through a so-called tholichthys larval interval characterized by elaborate, distinctive head spination:Coradion larvae have different head spination. While older chaetodontid larvae can be identified by adult characters, young (preflexion) larvae generally cannot now be identified below family. In tropical plankton studies chaetodontid larvae averaged <0.1% of larvae captured, and occurred in 13% of samples. This rarity is a major hindrance to further work, but is not unexpected in view of adult abundance. Larvae of a few taxa are most abundant in shelf waters, but larvae of many chaetodontid taxa seem to be most abundant in oceanic waters. In either case, waters near reefs have the fewest chaetodontid larvae. Offshore maxima of larvae appear to exist a few kilometers seaward of Great Barrier Reef ribbon reefs. Chaetodontid larvae may prefer the upper portion of the water column. Both size and age at settlement vary widely within the family and the large genusChaetodon, and the latter varies widely within species. Average size at settlement is less than 20 mm and age is less than 40 days. No correlation was found between size and age at settlement. Behaviour and feeding of chaetodontid larvae are essentially unstudied. Chaetodontid larvae seem to be least abundant in winter. The implications of these conclusions are discussed and some suggestions for further research are made. In all areas more work is needed.     

The mating behavior and reproduction performance in a multi-sire mating system for pigs

An important aim of organic animal production is to allow natural animal behaviour. Regarding reproduction techniques, artificial insemination is permitted but natural mating is preferred. The outdoor multi-sire system, where the sows are placed in large paddocks with a group of boars, is one example of a service system, which complies well with the organic ideals of facilitating natural animal behavior. However, very little knowledge is available about such system. Seven groups of in total of 47 sows and 31 boars were observed to study the mating behavior in an outdoor multi-sire mating system and the subsequent reproduction results. The time of start of courtship, behavior and the cause of disruption if the courtship was terminated, were recorded each time a boar courted a sow. All aggressive interactions between the boars were also recorded to estimate the boar ranking order. The observations revealed numerous poor quality matings, a huge variation in the number of times sows are mated, and overworked boars. Only 35% of all copulations lasted 2 min or more and 63% of all copulations were disrupted, mainly by competitor boars. The higher social status of the boar, the more copulations did it disrupt (p < 0.05). The outcome was an unacceptable variation in reproduction results. Only 71% of all estrus sows conceived, corresponding to a pregnancy rate of 77% of all mated sows. A large inter-group variation in reproduction performance was observed, indicating scope for improvements. In some groups all sows showed estrus and all sows conceived. Recommendations for improvement of the system are proposed.     

黑龙江省圈养狼交配行为的初步观察

2005 年10 月至2006 年4 月,采用焦点动物取样法和全事件扫描取样法,对黑龙江省哈尔滨北方森林动园4 对圈养狼交配活动进行了观察,以期了解无人干扰下圈养狼的交配过程及其交配模式。观察时间共计25 d, 225 h,实际录像时间为126 h,记录到爬跨741 次,成功交配46 次,成功爬跨交配占总爬跨次数的6. 2% 。狼在交配过程中有锁结现象,雄狼通常在一次爬跨、多次抽动后出现射精。交配行为一般发生在8∶ 00 ～10∶ 00和14∶00 ～ 16∶ 00。雌性具有明显的邀配模式,一旦邀配成功,雌狼站立不动,尾巴偏向一侧,腰部微下躬,配合雄狼爬跨。对交配参数进行单因素方差分析,4 只雄狼的抽插时间没有差异(P = 0. 827),而其锁结行为的时间差异极其显著(F = 71.43,P <0.001),交配期持续5 ～ 14 d,交配平均持续时间为534 ± 402 s,最长达1 588 s,
最短只有28 s。     

Hazel grouse (Bonasa bonasia) pairs during the nonbreeding season: mutual benefits of a cooperative alliance

During the nonbreeding season (autumn and winter), hazel grouse(Bonasa bonasia) males and females associate as loosely boundpairs, not as strongly bound pairs as previously thought. Thesepairs could be considered cooperative alliances, with each membergaining both direct and indirect benefits. The most importantdirect benefit appeared to be mutual vigilance against predators.This benefit was found at two levels: at the level of arborealfeeding sites, two birds could forage faster and farther fromcover than single birds, and at the territory scale, the pairwas together more in dangerous habitats. By foraging fartherfrom cover, two birds could use about 23% more of the preferredfood trees and 9%–10% more of the food available withina territory than a single bird, partially mitigating the costof having two birds feeding on limited winter food in the samespace. Defending a common territory appeared to be a less importantdirect benefit of the alliance because the members of a pairdid not defend the same territory and often associated withneighboring birds of the opposite sex. A future benefit of thealliance was having breeding partners in the spring; this wasmost beneficial for males, as the sex ratio was male biased.Members of the pair were often apart. At arboreal feeding sites,this separation was perhaps because the most preferred trees,black alders (Alnns glutinosa) with the most staminate catkins,were located in areas with the most cover, where one bird maybe safer from predators than two. Members of pairs in more securehabitats were more often with extrapair birds of the oppositesex. This suggested a trade-off; birds in safe habitats mayhave visited potential breeding partners, but birds in dangeroushabitats may have had to remain together, foregoing this option,to increase their survival probability. This social organizationappeared to be an adaptation to surviving in a heterogeneoushabitat, with some of the winter food located in dense coverand some located in more open and dangerous situations.     

Field and laboratory observations of spawning periodicity and behavior of a northern population of the Atlantic silverside,Menidia menidia (Pisces: Atherinidae)

Synopsis The spawning periodicity and mating behavior of a northern population of the Atlantic silverside, Menidia menidia, was studied both in the field (Salem Harbor, Massachusetts) and in laboratory experiments. Spawning in the field coincided with new and full moons. Under conditions of unlimited food availability in artificial outdoor pools that received natural celestial illumination or in indoor aquaria receiving no evening illumination, spawning occurred every 1–3 days rather than fortnightly. These results suggest that tidal influences are a primary factor that synchronizes spawning in M. menidia. Published reports of diel time of spawning in both marine and freshwater species of Menidia indicate a generic tendency to spawn during mid-morning. This pattern coupled with high tides that cover suitable spawning substrates during mid-morning only at fortnightly intervals could account for the semilunar spawning cycle in marine populations of Menidia. Although general characteristics of the reproductive ecology of M. menidia in Massachusetts were similar to a thoroughly studied population in South Carolina, several differences were evident. The breeding season was shorter in Massachusetts (late; April–June), and occurred over a much lower range of temperatures (9–21°C). Intensity and frequency of spawning was correlated with the height of high tide. Eggs were deposited only on mats of intertidal, filamentous algae rather than on roots or stems of Spartina alterniflora or other intertidal vegetation. Promiscuous spawning occurred in small, highly male-dominated groups of fish, primarily after the tide had begun to recede, and often at the water's edge. No predation on spawning adults was observed but the mummichog, Fundulus heteroclitus, fed daily on developing embryos during high tide. Contribution No. 81, Massachusetts Cooperative Fisheries Research Unit, Contribution No. 349, Marine Sciences Research Center, State University of New York at Stony Brook.     

圈养华南虎交配行为的初步观察

1 研究方法 1．1研究地点 在上海动物园虎山进行观察,虎山由半放养区和笼舍区构成。半放养区模仿野外环境,面积约250m^2。笼舍在半放养区后,共5间,每间由活动铁门隔开。     

Spawning behavior and reproductive isolation of two species ofPseudolabrus

The reproductive behavior of two wrasses,Pseudolabrus eoethinus (Richardson, 1846) andP. sieboldi Mabuchi & Nakabo, 1997, was studied on a rocky coast in Shikoku, Japan, where the two species occur sympatrically. In the study area, individual males of each species established mating territories within which pair spawnings occurred. Pair spawnings were observed only between conspecifics, indicating that the two coexisting species were reproductively isolated. Both species usually spawned during the afternoon in early winter and had similar reproductive behavior. Although habitat, temporal and behavioral isolation mechanisms were not apparent, reproductive isolation seemed to occur via premating isolation through visual recognition of conspecific mates because the two species differed in body size and coloration. On one occasion a maleP. sieboldi was observed to perform streaking behavior to join a spawning pair ofP. eoethinus. Thus, postmating isolation between the two species is also discussed.     

Comparative studies of social behavior in Callicebus and Saimiri: Behavioral and physiological responses of established pairs to unfamiliar pairs

The influences of cage size and novelty on the behavior of Galago senegalensis braccatus were examined in two captive groups (five adults and one immature per group) having similarly furnished but unequally sized cages. One group experienced expansion, and the other experienced contraction of space. Each group experienced the novelty of a new cage and return to its old cage. Exploration, nonsocial activity, and social sniffing behaviors were most frequent in both groups during the novelty phase independent of cage size. These behaviors remained elevated after return to the original cage. This pattern indicated that novelty, not space, was responsible for these behavioral changes. The increase in social sniffing indicated that group members may use olfactory cues to recognize each other, expecially when the setting is novel. In both groups, frequencies of displacements and chases were highest in the smaller space. Group differences in behavior prior to cage change also influenced a group's response to change.     

Size-dependent precopulatory behavior as mate-securing tactic in the Japanese stag beetle, Prosopocoilus inclinatus (Coleoptera; Lucanidae)

Males of the Japanese stag beetle Prosopocoilus inclinatus show dimorphism in body size. Since females frequently resist male courtship behavior, males often fail to mate after encounters with females. The males of two morphs showed different precopulatory behavior. During encounters with females, small males acted more persistently against females resistance than large males by grasping the female more solidly and as a result, succeeded in copulation more frequently. This persistent precopulatory behavior could be regarded as an alternative mating tactic of small males that are inferior to large males in direct physical competition.     

Mating tactics of male feral goats (Capra hircus): risks and benefits

Intense competition between males for reproduction has led to the evolution of alternative mating tactics (AMTs). Feral goat males usually use a tactic called tending, in which they defend oestrous females from other males. Males may also use a second mating tactic called coursing, in which they gain access to oestrous females by disturbing a tending pair. Herein, we examine estimated mating success (EMS) and risks of using these tactics. Tending was only used by mature (≥4 years old), higher-ranking males and accounted for 75% of EMS. Coursing was used by males of all ages and dominance ranks, and accounted for 25% of EMS. Using coursing, male kids achieved 8% of EMS. Mature males achieved 92% of EMS. Both age and dominance rank were related to EMS, but age was not important after its relationship with dominance was controlled. Tending bouts were, on average, ca. 30 min long, while coursing bouts only averaged ca. 2 min. Males were more likely to suffer a butt while coursing than while tending, and formerly tending males were responsible for most butts. Kids that coursed had the highest risk of being butted. In most AMTs, there are reductions in the risks in relation to low fitness benefits. However, we found that the risks of butts during coursing were high, while our evidence suggests that the EMS was probably low. Nevertheless, the existence of an effective AMT in male feral goats may have an important influence on the intensity of sexual selection and the effective population size.     

Active female courtship behavior and male nutritional contribution to female fecundity in Bruchidius dorsalis (Fahraeus) (Coleoptera: Bruchidae)

Mating behavior and the male's contribution to female fecundity were studied in the bean weevil Bruchidius dorsalis (Fahraeus) (Coleoptera: Bruchidae) in comparison with two other species, Callosobruchus chinensis (which infests stored beans) and Kytorhinus sharpianus (which feeds on wild legumes). Only females of B. dorsalis showed multiple mating and characteristic precopulatory behavior that appeared to solicit the male's nutritious secretion. In contrast, all females of the other two species did not copulate multiply and did not show such precopulatory behavior. In B. dorsalis, the decrement of male body weight just after copulation indicated that seminal fluid weighing as much as approximately 7% of the male's body weight was transferred to the female. Fecundity was more than eight times higher in females that had copulated ten times than in females that had copulated only once, indicating that males paid most of the nutritional cost of egg production. These facts suggest that the sex role is reversed in B. dorsalis. Received: May 22, 1998 / Accepted: July 19, 1999     

Mating behavior of ring-tailed lemurs (Lemur catta) at Berenty,Madagascar

The mating behavior of ring-tailed lemurs at Berenty, Madagascar, was observed in April 1982. Although Troop A included five adult females, only two were observed to mate. The mating period covered two consecutive days, April 24 and 25. Each female was receptive for about 4 hr. Data from 47 copulations, of which 38 were with ejaculation, suggest that to be the first mating partner is of importance for male ring-tailed lemurs. Previously it has been suggested that male dominance is of little significance in determining mating partners. In this investigation it was observed that the second most dominant male MK was always the first mating partner. Only after several ejaculations and resultant fatigue did he lose possession of the female to lower ranking males, and the first ranking male was not seen to copulate with either female at any time. These results suggest that a male's mating success is partly, but not completely correlated with his dominance rank, and that other factors, including his length of residence in the group and female choice, also determine patterns of mating.