VESSEL COLLISIONS WITH WHALES: THE PROBABILITY OF LETHAL INJURY BASED ON VESSEL SPEED

Historical records demonstrate that the most numerous, per capita, ocean-going-vessel strikes recorded among large-whale species accrue to the North Atlantic right whale ( Eubalaena glacialis ). As vessel speed restrictions are being considered to reduce the likelihood and severity of vessel collisions with right whales, we present an analysis of the published historical records of vessels striking large whales. We examine the influence of vessel speed in contributing to either a lethal injury (defined as killed or severely injured) or a nonlethal injury (defined as minor or no apparent injury) to a large whale when struck. A logistic regression model fitted to the observations, and consistent with a bootstrap model, demonstrates that the greatest rate of change in the probability of a lethal injury ( P _lethal) to a large whale occurs between vessel speeds of 8.6 and 15 knots where P _lethal increases from 0.21 to 0.79. The probability of a lethal injury drops below 0.5 at 11.8 knots. Above 15 knots, P _lethal asymptotically approaches 1. The uncertainties in the logistic regression estimates are relatively large at relatively low speeds ( e.g. , at 8 knots the probability is 0.17 with a 95% CI of 0.03–0.6). The results we provide can be used to assess the utility of vessel speed limits that are being considered to reduce the lethality of vessels striking the critically endangered North Atlantic right whale and other large whales that are frequent victims of vessel strikes.     

Faecal soiling and gastrointestinal helminth infection in lambs

The accumulation of faeces in the wool of the breech area (tail, perineum and anus) of lambs, known as faecal soiling, has been shown to be one of the major factors predisposing sheep to blowfly strike. However, the causes of faecal soiling of lambs in the UK are not clearly understood. Hence, in this investigation, the relationships between faecal soiling, gastrointestinal parasitic nematode infection and resultant diarrhoea were examined in a longitudinal study of 200 lambs at two farms in south-west England. Faecal egg counts, pasture worm burdens, faecal soiling and growth rates were recorded for individually tagged lambs over the summer of 2003. Grass growth and nutritional composition (protein and fibre) and weather data were also recorded over this period. Analysis using linear mixed models showed that faecal soiling was associated with higher strongyle-type egg counts, longer periods since worming, lower live-weights, female gender, lower faecal consistency and pasture quality. The data indicate that dag scoring, especially in mid- to late summer, could be used as a rapid, non-invasive technique for selecting animals, particularly lambs, with high faecal egg counts for selective drenching to reduce the incidence of anthelmintic resistance. Selective drenching of lambs with high dag scores would also be expected to aid in the control of blowfly strike.     

Have the Harmful Effects of Introduced Rats on Islands been Exaggerated?

Introduced rats are now being eradicated from many islands. Increasingly, these eradications are contested by activists claiming moral, legal, cultural, historic or scientific reasons and poorly documented evidence of effects. We reviewed the global literature on the effects of rats on island flora and fauna. We then used New Zealand as a case study because of its four-decade history of rat eradications and many detailed and innovative studies of how rats affect native species. These include use of exclosures, local manipulations of rat populations, video surveillance, and measurements of responses following eradications. The most intensive studies have been on the Pacific rat (Rattus exulans), a small South-East Asian species spread by Polynesians throughout the Pacific. These and the more recently introduced Norway rat (R. norvegicus) and ship (roof) rat (R. rattus) suppress some forest plants, and are associated with extinctions or declines of flightless invertebrates, ground-dwelling reptiles, land birds, and burrowing seabirds. On islands off France, Norway rats are also implicated in declines of shrews. Globally, ship rats were associated with declines or extinctions of the largest number of indigenous vertebrate species (60), including small mammals such as deer mice and bats. Effects of rats on forest trees and seabird populations are sufficiently pervasive to affect ecosystem structure and function. However, the data are patchy. Deficiencies in our knowledge would be reduced by documenting distribution and abundance of indigenous species before and after eradications. Comprehensive measurements of the responses of indigenous species to rat eradications would enable the development of testable models of rat invasion effects.     

Host-parasite coevolution induces selection for condition-dependent sex

Sex and recombination remain one of the biggest riddles of evolutionary biology. One of the most prominent hypotheses, the Red Queen Hypothesis, claims that sex has evolved as a means to efficiently create genotypes that are resistant against coevolving parasites. However, previous models of the Red Queen have assumed that all individuals are equally likely to engage in sexual reproduction, regardless of their infection status, an assumption that may not be true in reality. Here, we consider a population genetic model of a host population coevolving with a parasite population, where the parasites are haploid and the hosts either haploid or diploid. We assume that the probability to engage in sex may be different in infected and uninfected hosts and ascertain the success of different reproductive strategies with a modifier-gene approach. Our model shows that in the large majority of the parameter space, infection-dependent sex is more successful than infection-independent sex. We identify at least two reasons for this: (i) an immediate short-term advantage of breaking-down gene combinations of unfit individuals and (ii) a selfish spread of the condition-dependent modifiers, in analogy to the 'abandon-ship' effect in single species. In diploids, these effects are often powerful enough to overcome the detrimental effects of segregation. These results raise the intriguing question of why infection-induced sex is not more commonly observed in nature.     

Quantification of bird migration by radar – a detection probability problem

Besides the scientific interest in the quantification of bird migration, there is an increasing need to quantify bird movements for the assessment of bird collision risk with artificial structures. In many environmental impact studies, the radar method is used in an inappropriate manner. The processing of echoes consists often of counting blips within defined screen fields, and the surveyed volume is estimated without reference to the detection probabilities of different 'target sizes' (radar cross-sections). The aim of this paper is to present a procedure to quantify bird migration reliably using radar by stating the theoretical requirements of every single step of this procedure and presenting methodological solutions using our own radar data from extensive field studies. Our methodological solutions can be applied to various radar systems, including widely used ship radar. The procedure presented involves discriminating the echoes of birds and insects and estimating the different detection probabilities of differently 'sized' birds (radar cross-sections). By ignoring the different detection probabilities, density estimations may be wrong by as much as 400%. We fear that quantification of bird migration and predicted bird numbers affected by collisions with artificial structures are in many cases based on unreliable estimates.     

The impact of introduced ship rats (Rattus rattus) on seedling recruitment and distribution of a subantarctic megaherb (Pleurophyllum hookeri)

Abstract The impact of introduced ship rats (Rattus rattus) on recruitment of the megaherb Pleurophyllum hookeri Buchan. (Asteraceae) was examined on subantarctic Macquarie Island, an island with no extant native terrestrial vertebrates. Pleurophyllum hookeri (Asteraceae) forms a dominant component of the Macquarie Island vegetation and is restricted to the subantarctic. The Macquarie Island population of P. hookeri is the most extensive and intact. Introduced ship rats (Rattus rattus) are well established in tall tussock grassland of Macquarie Island. We detected rat activity for the first time within P. hookeri herbfields, in autumn 2000. We found rats were destroying up to 90% of racemes. By excluding rats from caches of inflorescences that they had formed, we found they were having a significant negative effect on initial recruitment and seedling survival within the caches. However, because of high seedling mortality after 1 year, there was no sustained impact of the exclosures on P. hookeri seedling density.     

机场周边家鸽飞行行为的潜在鸟击风险初步研究

鸟击防控是一个世界性难题。家鸽（Columba livia domestica）是机场生物多样性调查中最常见鸟类,也是历史上鸟击高危物种之一,还是唯一由于人工大量放飞导致严重鸟击事故的物种。2020年9月至2021年1月,在我国4个机场,针对机场周边23家鸽户,共149只家鸽开展卫星追踪放飞实验研究,获得了家鸽个体在机场周边的飞行时间、飞行距离、飞行高度等个体运动参数。研究发现,1）单次放飞时长多在1 ~ 4 h,单次平均放飞时长为（2.9 ± 1.6）h。在鸽户自主放飞家鸽和家鸽自由回笼的动态过程中,下午活动在外的家鸽数量较多,尤其15:00 ~ 17:59时段是活动在外家鸽数量最多的时段。2）飞行距离多在3.0 km范围内,最远可达8.9 km;存在家鸽飞行范围覆盖机场现象的鸽户占比45%。3）飞行高度主要在200 m及以下,平均飞行高度为（29 ± 28）m。本研究结果表明,下午,尤其是15:00 ~ 17:59时段应作为家鸽防控的重点时段,机场周边10 km以及高度0 ~ 200 m的范围应作为家鸽防控的重点空间范围。根据《中华人民共和国民用航空法（2021修正）》第五十八条明确规定“不得饲养、放飞影响飞行安全的鸟类动物和其他物体”,需要建立相应的问责机制、加强有效监管,以降低家鸽鸟击风险。     

Growth and differentiation signals regulated by the M-CSF receptor

The normal proto-oncogene c-fms encodes the macrophage growth factor (M-CSF) receptor involved in growth, survival, and differentiation along the monocyte-macrophage lineage of hematopoietic cell development. A major portion of our research concerns unraveling the temporal, molecular, and structural features that determine and regulate these events. Previous results indicated that c-fms can transmit a growth signal as well as a signal for differentiation in the appropriate cells. To investigate the role of the Fms tyrosine autophosphorylation sites in proliferation vs. differentiation signaling, four of these sites were disrupted and the mutant receptors expressed in a clone derived from the myeloid FDC-P1 cell line. These analyses revealed that: (1) none of the four autophosphorylation sites studied (Y697, Y706, Y721, and Y807) are essential for M-CSF-dependent proliferation of the FDC-P1 clone; (2) Y697, Y706, and Y721 sites, located in the kinase insert region of Fms, are not necessary for differentiation but their presence augments this process; and (3) the Y807 site is essential for the Fms differentiation signal: its mutation totally abrogates the differentiation of the FDC-P1 clone and conversely increases the rate of M-CSF-dependent proliferation. This suggests that the Y807 site may control a switch between growth and differentiation. The assignment of Y807 as a critical site for the reciprocal regulation of growth and differentiation may provide a paradigm for Fms involvement in leukemogenesis, and we are currently investigating the downstream signals transmitted by the tyrosine-phosphorylated 807 site. In Fms-expressing FDC-P1 cells, M-CSF stimulation results in the rapid (30 sec) tyrosine phosphorylation of Fms on the five cytoplasmic tyrosine autophosphorylation sites, and subsequent tyrosine phosphorylation of several host cell proteins occurs within 1–2 min. Complexes are formed between Fms and other signal transduction proteins such as Grb2, Shc, Sos1, and p85. In addition, a new signal transduction protein of 150 kDa is detectable in the FDC-P1 cells. The p150 is phosphorylated on tyrosine, and forms a complex with Shc and Grb2. The interaction with Shc occurs via a protein tyrosine binding (PTB) domain at the N-terminus of Shc. The p150 is not detectable in Fms signaling within fibroblasts, yet the PDGF receptor induces the tyrosine phosphorylation of a similarly sized protein. In hematopoietic cells, this protein is involved in signaling by receptors for GM-CSF, IL-3, KL, MPO, and EPO. We have now cloned a cDNA for this protein and found at least one related family member. The related family member is a Fanconia Anemia gene product, and this suggests potential ways the p150 protein may function in Fms signaling. Mol Reprod Dev 46:96–103, 1997. © 1997 Wiley-Liss, Inc.     

The effects of grooming on a copper ablative coating: a six year study

More than 90% of US Navy Ships are coated with copper ablative paint. These ships may spend long periods of time pier-side, which makes them vulnerable to fouling. Hull grooming has been proposed as a means of maintaining the coatings in an operational condition. This study investigated the effect of grooming on a copper ablative coating exposed statically for six years. Grooming was performed weekly or monthly with controls left ungroomed. The fouling community was visually assessed, dry film thickness measurements were taken to monitor coating loss, and the copper leaching rates were measured. It was found that weekly and monthly groomed surfaces reduced fouling, and the ungroomed surfaces became fully fouled. Coating loss was similar for weekly, monthly and ungroomed surfaces. The results suggest that grooming is a viable method for maintaining copper ablative coatings in a fouling-free condition without adverse increases in the total copper output.     

Consequences of injuries on survival and reproduction of common bottlenose dolphins (Tursiops truncatus) along the west coast of Florida

Accurate identification of human‐induced injuries that lead to death or interfere with reproduction is important for marine mammal management, as deaths exceeding established limits can lead to restrictions on fisheries or vessel operations. The fates of cetaceans last seen swimming with attached gear, particularly in pelagic fisheries, or with vessel strike lacerations, have been difficult to predict. Survival and reproduction data from long‐term research on resident common bottlenose dolphins near Sarasota, Florida were examined relative to consequences of fishing gear ingestion, line entanglements, vessel strikes, and amputations of unknown origins. Fishing hooks embedded in the throat, goosebeak, or esophagus, or line wrapped around the goosebeak, generally lead to death. Multiple, constrictive line wraps around fin insertions can lead to amputation, blood loss, impaired mobility, or infection. Dolphins with ingested gear or severe entanglements may swim away with the gear, but likely die later. Propeller injuries involving only soft tissue were often survivable. Some dolphins survived amputations of the distal ends of fins, and continued to reproduce. As a precautionary approach, dolphins with ingested gear or severe constrictive entanglements should be considered mortalities, but extrapolations of findings from coastal bottlenose dolphins to other cetaceans and different gear must be done with caution.