Gonadal and hormonal phenology in free-living male rufous whistlers, Pachycephala rufiventris (Passeriformes : Pachycephalidae)

2001 ◽  
Vol 49 (6) ◽  
pp. 651 ◽  
Author(s):  
P. G. McDonald ◽  
L. B. Astheimer ◽  
W. A. Buttemer

The hormonal and gonadal profiles of the few Australian old endemic passerine species studied to date have exhibited less annual variation in gonad size, reduced amplitude in testosterone (T) and luteinising hormone (LH) levels in comparison with those exhibited by many predominantly migratory species from the north temperate zone. Because none of the Australian endemics studied to date were migratory species, we studied a migratory population of rufous whistlers in central western New South Wales to determine whether differences in life history might be associated with different gonadal and hormonal profiles. Breeding stages were classified into five functional categories: territory/pair establishment, nest building, incubation, feeding nestlings/fledglings and post-breeding. We captured adult males at all breeding stages, examined their gonadal status through unilateral laparotomy, collected a blood sample and assessed this for plasma T and LH content using radioimmunoassay. Both hormones peaked early in the breeding season: LH levels during territory/pair establishment at 2.8 ng/mL 1.7 (s.d.) and T levels during nest building at 1.8 ng/mL 1.6 (s.d.). Following incubation LH and T (in particular) levels decreased substantially with the onset of parental duties – whilst feeding nestlings/fledglings T was 0.1 ng/mL 0.1 (s.d.), and LH was 1.6 ng/mL 1.2 (s.d.). This temporal variation in hormone secretion and an observed synchronous peak in gonad size at nest-building is reminiscent of migratory species from the north temperate zone displaying biparental care. Peak concentrations of both plasma T and LH in whistlers were intermediate between those reported for passerines from the north temperate zone with a similar life history and sedentary Australian old endemic passerines examined to date. This possibly reflects differences in life-history traits, the functional use of T in this species and/or possible phyletic effects.

1988 ◽  
Vol 66 (8) ◽  
pp. 1752-1762 ◽  
Author(s):  
Kristiina Ovaska ◽  
Thomas B. Herman

We examined abundance, reproduction, movements, and adult–juvenile interactions of Napaeozapus insignis in a 5-year mark–recapture study in Nova Scotia. Densities of N. insignis varied greatly between years, mainly as a result of variation in overwintering survival of juveniles and breeding success of females. Year-to-year survival rates of adults were relatively constant (approximately 26%), whereas those of juveniles fluctuated widely. Adult females produced only one litter per season, and no juvenile reproduced in the summer of her birth. Length of the active season was 12–17 weeks, and timing of emergence from hibernation varied little from year to year. Males emerged from hibernation 15–33 days earlier than females, and their captures were clustered along portions of the transects adjacent to steep slopes, which may have provided well-drained hibernation sites. The overall sex ratio did not differ from 1:1, but in May it was biased towards males, and in July and August adult females outnumbered adult males. Distances moved by adult males and females within 24 h were similar (mean for males = 97 m, for females = 61 m), but home ranges of males between June and August were greater than those of females (mean distance between two farthest captures for males = 447 m, for females = 175 m). Results from a removal experiment, as well as examination of trapping records, indicated that adult females inhibited early capture of juveniles when densities of adults were high. We suggest that the suite of life history traits (long life-span, late maturity, infrequent reproduction) that northern zapodids exhibit relative to southern zapodids is best explained by a bet-hedging hypothesis. Long winters and short summers in the north contribute to low and unpredictable overwintering survival of juveniles. By directing energy from reproduction into accumulation of hibernation fat, adults increase their chances of surviving to breed again the next summer and thus decrease the probability of leaving no young at all.


1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.


1979 ◽  
Vol 15 (2) ◽  
pp. 176-188 ◽  
Author(s):  
Philip Jenkins

In the seventeenth century, one of the Catholic strongholds of Britain had lain on the southern Welsh borders, in those areas of north Monmouthshire and southern Herefordshire dependant on the Marquis of Worcester at Raglan, and looking to the Jesuit mission at Cwm. Abergavenny and Monmouth had been largely Catholic towns, while the north Monmouthshire countryside still merited the attention of fifteen priests in the 1670s—after the Civil Wars, and the damaging conversion to Protestantism of the heir of Raglan in 1667. Conspicuous Catholic strength caused fear, and the ‘Popish Plot’ was the excuse for a uniquely violent reaction, in which the Jesuit mission was all but destroyed. What happened after that is less clear. In 1780, Berington wrote that ‘In many [counties], particularly in the west, in south Wales, and some of the Midland counties, there is scarcely a Catholic to be found’. Modern histories tend to reflect this, perhaps because of available evidence. The archives of the Western Vicariate were destroyed in a riot in Bath in 1780, and a recent work like J. H. Aveling's The Handle and the Axe relies heavily on sources and examples from the north of England. This attitude is epitomised by Bossy's remark on the distribution of priests in 1773: ‘In Wales, the mission had collapsed’. However, the question of Catholic survival in eighteenth-century Wales is important. In earlier assessments of Catholic strength (by landholding, or number of recusants gaoled as a proportion of population) Monmouthshire had achieved the rare feat of exceeding the zeal of Lancashire, and Herefordshire was not far behind. If this simply ceased to exist, there was an almost incredible success for the ‘short, sharp’ persecution under Charles II. If, however, the area remained a Catholic fortress, then recent historians of recusancy have unjustifiably neglected it.


Oceania ◽  
1957 ◽  
Vol 27 (3) ◽  
pp. 190-209 ◽  
Author(s):  
Malcolm J. C. Calley

Author(s):  
Conor Ryan ◽  
Pádraig Whooley ◽  
Simon D. Berrow ◽  
Colin Barnes ◽  
Nick Massett ◽  
...  

Knowledge on the ecology of humpback whales in the eastern North Atlantic is lacking by comparison with most other ocean basins. Humpback whales were historically over-exploited in the region and are still found in low relative abundances. This, coupled with their large range makes them difficult to study. With the aim of informing more effective conservation measures in Ireland, the Irish Whale and Dolphin Group began recording sightings and images suitable for photo-identification of humpback whales from Irish waters in 1999. Validated records submitted by members of the public and data from dedicated surveys were analysed to form a longitudinal study of individually recognizable humpback whales. The distribution, relative abundance and seasonality of humpback whale sighting records are presented, revealing discrete important areas for humpback whales in Irish coastal waters. An annual easterly movement of humpback whales along the southern coast of Ireland is documented, mirroring that of their preferred prey: herring and sprat. Photo-identification images were compared with others collected throughout the North Atlantic (N = 8016), resulting in matches of two individuals between Ireland and Iceland, Norway and the Netherlands but no matches to known breeding grounds (Cape Verde and West Indies). This study demonstrates that combining public records with dedicated survey data is an effective approach to studying low-density, threatened migratory species over temporal and spatial scales that are relevant to conservation and management.


2006 ◽  
Vol 285 (1-2) ◽  
pp. 245-255 ◽  
Author(s):  
M. T. McHenry ◽  
B. R. Wilson ◽  
J. M. Lemon ◽  
D. E. Donnelly ◽  
I. G. Growns

2001 ◽  
Vol 126 (2) ◽  
pp. 219-224 ◽  
Author(s):  
H. M. PALMER ◽  
J. P. LEEMING ◽  
A. TURNER

Ciprofloxacin-resistant gonococci have been isolated from patients in the United Kingdom since 1993. Until recently, evidence has suggested that the majority of infections are not endemic but have been acquired abroad. In October 1999, increasing numbers of ciprofloxacin resistant isolates of the non-requiring auxotype were reported in Oldham and Rochdale (Northwest England). These and similar isolates from elsewhere in England and Wales were genetically characterized using a simplified opa-typing method (a non-radioactive PCR–RFLP method targeting the opa family of genes). Of 73 isolates studied, 24 had unique opa-types (10 from infections acquired abroad), whilst the remaining 49 were indistinguishable (none were known to be acquired abroad). This cluster included 31 isolates from Oldham and Rochdale, 16 from elsewhere in the north of England, and 2 from Southern England and South Wales with known epidemiological links to cases from Manchester and Rochdale respectively. This study illustrates the potential for spread of an antibiotic resistant clone of N. gonorrhoeae both locally and nationally and demonstrates that endemic acquisition of ciprofloxacin-resistant gonococci is now a significant problem in the United Kingdom.


1963 ◽  
Vol 29 ◽  
pp. 99-132 ◽  
Author(s):  
G. J. Wainwright

The distribution of Mesolithic sites in Wales is controlled to a great extent by the terrain, for physiographically, Wales is a highland block defined on three sides by the sea and for the greater part of the fourth side by a sharp break of slope. Geologically the Principality is composed almost entirely of Palaeozoic rocks, of which the 600-foot contour encloses more than three quarters of the total area. There are extensive regions above 1,500 feet and 2,000 feet and in the north the peaks of Snowdonia and Cader Idris rise to 3,560 feet and 2,929 feet respectively. Indeed North Wales consists of an inhospitable highland massif, skirted by a lowland plateau and cut deeply by river valleys, providing only limited areas for settlement. The hills and mountains of Snowdonia with their extension at lower altitudes into the Lleyn Peninsula, and the ranges of Moelwyn, Manod Mawr, Arenig Fach and Cader Idris, are discouraging obstacles to penetration, save for a short distance along the river valleys. To the east of these peaks are extensive tracts of upland plateau dissected by rivers, bounded on the west by the vale of the river Conway and cleft by the Vale of Clwyd. To the east of this valley lies the Clwydian Range and further again to the east these uplands descend with milder contours to the Cheshire and Shropshire plains.To the south the district merges into the uplands of Central Wales, which are continuous until they are replaced by the lowland belt of South Wales.


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