Population trends for humpback whales (Megaptera novaeangliae) foraging in the Francisco Coloane Coastal‐Marine Protected Area,Magellan Strait,Chile

In 2003 a feeding aggregation of southeastern Pacific humpback whales (Megaptera novaeangliae) was reported in the Magellan Strait. While Chile established its first marine national park in the Strait to protect humpback whale habitat, fatal ship strikes remain a concern because of overlap with a busy shipping lane. To better understand population risk, we estimated abundance and survival for this population using Bayesian robust‐design mark‐recapture models fit to photographic data from 2004 to 2016. Overall, the model estimated a total of 204 whales (95% CI: 199–210) during the last 12 yr, and 93 (95% CI: 86–100) in the 2016/2017 austral summer. The population grew at 2.3% (CI: 2.1%–3.1%), an annual increase of two whales. Annual survival (including calves) was estimated at 0.892 (CI: 0.871–0.910). Our results corroborate a persistent feeding population, but one that is increasing relatively slowly. Owing to its vulnerability stemming from its small size, coupled with significant overlap with a busy shipping lane, we argue this subpopulation is at significant risk from ship strikes and may be one of the few populations where anthropogenic mortalities could regulate population dynamics. We therefore encourage continued monitoring via photographic mark‐resighting surveys, and analyses explicitly investigating potential population‐level ship strike effects.     

Enhanced adhesion and chemoattraction of zoospores of the fouling alga enteromorpha to some foul‐release silicone elastomers

Significantly higher numbers of zoospores of the fouling, green alga Enteromorpha adhered to silicone elastomers cured by dibutyltin dilaurate (DBTDL) than to identical polymers cured by dibutyltin diacetate (DBTDA). Enhanced zoospore adhesion was shown to be due to the presence of DBTDL and the effect was concentration‐dependent. Further experiments revealed that enhanced zoospore adhesion also occurred to glass coverslips coated with lauric acid (C₁₂) and other saturated fatty acids. The possibility that fatty acids may act as chemical cues (chemoattractants), guiding motile zoospores to the substratum for settlement in the natural environment is discussed. Settlement of other fouling organisms to DBTDL‐cured silicone elastomers is currently being investigated.     

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.     

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。     

Aeroecology meets aviation safety: early warning systems in Europe and the Middle East prevent collisions between birds and aircraft

The aerosphere is utilized by billions of birds, moving for different reasons and from short to great distances spanning tens of thousands of kilometres. The aerosphere, however, is also utilized by aviation which leads to increasing conflicts in and around airfields as well as en‐route. Collisions between birds and aircraft cost billions of euros annually and, in some cases, result in the loss of human lives. Simultaneously, aviation has diverse negative impacts on wildlife. During avian migration, due to the sheer numbers of birds in the air, the risk of bird strikes becomes particularly acute for low‐flying aircraft, especially during military training flights. Over the last few decades, air forces across Europe and the Middle East have been developing solutions that integrate ecological research and aviation policy to reduce mutual negative interactions between birds and aircraft. In this paper we 1) provide a brief overview of the systems currently used in military aviation to monitor bird migration movements in the aerosphere, 2) provide a brief overview of the impact of bird strikes on military low‐level operations, and 3) estimate the effectiveness of migration monitoring systems in bird strike avoidance. We compare systems from the Netherlands, Belgium, Germany, Poland and Israel, which are all areas that Palearctic migrants cross twice a year in huge numbers. We show that the en‐route bird strikes have decreased considerably in countries where avoidance systems have been implemented, and that consequently bird strikes are on average 45% less frequent in countries with implemented avoidance systems in place. We conclude by showing the roles of operational weather radar networks, forecast models and international and interdisciplinary collaboration to create safer skies for aviation and birds.     

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.     

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.     

The ghost of fouling communities past: the effect of original community on subsequent recruitment

Biofouling on ships has been linked to the spread of invasive species, which has been identified as one of the current primary threats to the environment. Previous research on antifouling coatings suggested that the quantity of fouling, as well as community composition, on biocidal coatings was modified by prior fouling settlement. The experiment reported in this paper was designed to determine how preconditioning affected the rate and composition of subsequent fouling on transplanted silicone coatings. A series of 10 × 20?cm panels coated with Intersleek 700 or DC3140 were placed at three locations in Florida (Ponce Inlet, Sebastian Inlet, and Port of Miami), which were characterized by distinct fouling communities. Panels were immersed for four months, cleaned, and reciprocally transplanted among the three sites. Fouling community composition and coverage were characterized at bimonthly intervals both before and after transplantation. The original fouling community affected the subsequent fouling composition and recolonization by tunicates, sea anemones, barnacles, sponges, hydroids, and arborescent bryozoans. The community-level effects were short-term, lasting 2–4?months, but specific responses lasted up to 14?months post-transplant.     

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.     

Small mammals as potential seed dispersers in New Zealand

Weed invasion success is strongly influenced by availability of seed dispersal vectors, which may include animals. We examined the potential of several small introduced mammals (mice, kiore, ship rats and possums) to disperse germinable seeds in New Zealand. Captive animals were fed fleshy fruit of weeds (Berberis glaucocarpa, Cotoneaster spp., Crataegus monogyna, Ilex aquifolium, Leycesteria formosa, Ligustrum sinense, Lonicera japonica, Passiflora mollissima, Pyracantha angustifolia, Sorbus hupehensis) and native species (Coprosma spp., Prumnopitys ferruginea and Solanum aviculare). We recorded the percentage of fruit consumed, seed ingested and gut passage time. Faeces were collected and the seeds extracted and tested for germination potential in an unheated glasshouse (two weed species) or under controlled conditions (11 species). The smallest rodents (mice and kiore) generally destroyed all seeds eaten. Large numbers of viable seeds of the small‐seeded (<1 mg) species, L. formosa and S. aviculare, passed through ship rats. Possums consumed the seeds of all adventive and native fruits except P. ferruginea. The proportion of seeds recovered intact from possum faeces varied with plant species and ranged from 6 to 83%. The time required for 50% of all seeds to be passed by possums ranged from 2.5 to 5.5 days with an average of 3.7 days, and was generally unrelated to simple fruit parameters such as percentage pulp and moisture content. For seeds where germination also occurred in the uneaten controls, the germination of seed from possums ranged from 3 to 78%. Germination was mostly lower in seeds from possums than in the controls, where differences were significant. Possums have major potential to disperse a wide range of fleshy fruit‐producing native and introduced plant species. Ship rats have the potential to disperse those with very small seeds.