Homing Instinct Research Articles

Archaeogenomic analysis of Chesapeake Atlantic sturgeon illustrates shaping of its populations in recovery from severe overexploitation.

Atlantic sturgeon (Acipenser oxyrinchus ssp. oxyrinchus) has been a food resource in North America for millennia. However, industrial-scale fishing activities following the establishment of European colonies led to multiple collapses of sturgeon stocks, driving populations such as those in the Chesapeake area close to extinction. While recent conservation efforts have been successful in restoring census numbers, little is known regarding genomic consequences of the population bottleneck. Here, we characterize its effect on present-day population structuring and genomic diversity in James River populations. To establish a pre-collapse baseline, we collected genomic data from archaeological remains from Middle Woodland Maycock's Point (c. 200-900 CE), as well as Jamestown and Williamsburg colonial sites. Demographic analysis of recovered mitogenomes reveals a historical collapse in effective population size, also reflected in diminished present-day mitogenomic diversity and structure. We infer that James River fall- and spring-spawning populations likely took shape in recent years of population recovery, where genetic drift enhanced the degree of population structure. The mismatch of mitogenomic lineages to geographical-seasonal groupings implies that despite their homing instinct and differential adaptation manifested as season-specific behaviour, colonization of new rivers has been a key ecological strategy for Atlantic sturgeon over evolutionary timescales.

Animals’ Mobilities in Popular Fiction: Time, Duration, and Desire in Sheila Burnford’s The Incredible Journey

Abstract In Sheila Burnford’s 1961 novel The Incredible Journey, three domestic animals undertake an arduous trek through the forests of northern Ontario to be reunited with their owners and family. As an example of “homing instinct” stories, The Incredible Journey has been influential, notably as a result of the 1963 Disney film. The genre is easily dismissed as sentimentally anthropomorphic, but this paper treats Burnford’s novel as a sophisticated treatment of animals’ mobilities in terms of literary animal studies. Drawing on the philosophy of Henri Bergson, The Incredible Journey is presented as an adventure in time rather than in space, contrasting the human perspective of maps and miles with the Bergsonian concept of duration, the real experience of the passage of time, and with related themes of free will, instinct, and desire. This paper concludes that Burnford offers a less anthropocentric perspective on animals’ mobility.

The reentry of Asian kinesiology professionals after obtaining a doctorate at higher education institutions in the U.S.

With the large increase in international doctorates at higher education institutions in the United States, little attention is being paid to former doctoral students’ cross-cultural experiences during their reentry to their home countries. Based on the re-acculturation theory as a conceptual framework, this qualitative inquiry aimed to explore how study participants perceive their reentry. The findings were explained using six subthemes: (a) the renewal process, (b) ambivalence of reentry, (c) homing instinct, (d) environmental context, (e) midpoint of repatriation, and (f) different research atmospheres. The findings reveal the importance of doctorates’ flexibility to cope with each country’s academic atmosphere and respect academic cultural differences. The findings provide insight into the challenges that international kinesiology professionals face during their reentry and how they resolve these difficulties for readjustment to the academic atmosphere of their home countries.

Versatile monarch butterflies can switch navigation strategy

While the logistics of international travel remain off-putting as the Covid-19 pandemic ebbs and flows, creatures that routinely circumnavigate oceans and continents have continued undaunted. Arctic terns are still smashing long distance records while wildebeest move en masse in colossal herds. But the sovereign of the multigenerational migration has to be the monarch butterfly. Each spring, the original pioneers depart their overwintering grounds in Mexico for their Canadian summer home, yet it is their great-great-great-grandchildren that return ∼8 months later. ‘To keep a constant direction over this enormous distance, these animals rely on the sun for orientation’, says Myriam Franzke from the University of Wuerzburg, Germany. However, when the insects near their final destination, they may switch to other forms of guidance to select their ultimate landing site. Yet, no one had tested whether monarch butterflies can use other forms of navigation, beyond being directed by the sun, so Franzke, Christian Kraus, Maria Gayler, Keram Pfeiffer and Basil el Jundi, from the University of Wuerzburg, with David Dreyer from Lund University, Sweden, teamed up to test out the insect's homing instinct.‘We ordered the butterfly pupae from Costa Rica where they were raised in captivity’ says el Jundi, recalling that the adults began emerging from their chrysalises 3 days after their arrival in Germany. ‘It is always a remarkable moment when the small chrysalises turn into colourful butterflies with large wings’, says Franzke. Next, the team gently tethered individual butterflies at the centre of a cylindrical flight arena, allowing the insects to swivel in any direction as they took to the wing. Then, the scientists tested which directions the insects selected when they illuminated LEDs lining the wall of the arena, providing the insects with different views.Switching off three LED columns to show a 4 cm wide vertical dark band against a bright background, the team filmed the butterflies’ manoeuvres for 8 min, switching the position of the bar to the opposite side of the arena from time to time to make sure that the insects were still paying attention. Although the butterflies took hardly any notice of the bar initially, swivelling continually in different directions, by the end they were occasionally holding a steady direction toward one edge of the bar, before veering off again.In contrast, the monarchs seemed far more fixated by a bright vertical bar against a dark background. Some flew directly toward the light for the full 8 min, only switching direction when the bar shifted spontaneously to the other side of the arena: they were definitely attracted to the bright object. But how would the insects fare when the team presented them with a single illuminated green LED, which the butterflies mistake for the sun?This time, the insects set a bearing relative to the fake sun and tended to keep to that path, rotating through 180 deg each time the simulated sun jumped to the other side of the arena. They were using the bright light as a compass guiding their choice of direction, as if they were dispersing toward Canada or returning to Mexico to overwinter. And when the researchers alternated the bright vertical bar with the simulated sun, the butterflies flew persistently toward the bar, but switched direction and set a bearing when the fake sun flashed into view.‘[Monarch] butterflies can switch between compass orientation and attraction’, says el Jundi, and the team suspects that the insects depend on specialised guidance circuits in the brain when navigating over long distances by the sun, but have the ability to switch with ease and simply gravitate toward an object when close to home.

Enhancement in seed production of Pearlspot, Etroplus suratensis (Bloch) through improvisation in rearing techniques

ABSTRACT Three seed production techniques of pearlspot Etroplus suratensis (Bloch)—pond rearing, tank rearing, and pit rearing—were evaluated in farmers’ fields to assess production success, practicality, and economic viability. The pond rearing technique stocked mature pearlspot in ponds with artificial substrates and reared seed in the pond itself. The tank rearing technique collected pearlspot eggs from the pond and hatched and reared them in separate tanks. The pit rearing technique trapped pearlspot fry using a specially designed falling trap and reared them in ponds with an artificial feed. The average fingerlings productions per spawning per pair were 47 ± 27, 93 ± 22, and 578 ± 82 respectively. The pit rearing technique was reported to be preferred by farmers because of its ease and cost effectiveness. The homing instinct of pearlspot brooders with spawn to the nursing pits was observed even weeks after hatching.

Homing Instinct

Homing Instinct

Zhang-Zai(張載)’s Sky Theory(渾天說) and Taekwondo Training within Energy(氣)

This study started with the aim of understanding Energy(氣) in taekwondo training based on the Sky Theory(渾天說) by an Eastern philosopher from Song Dynasty(宋代) named Zhang-Zai (張載). His book, “Correcting Youthful Ignorant(正蒙),” was reviewed in order to interpret the meaning of taekwondo, as Eastern martial arts, based on his philosophy. It is concluded as follows: The Sky Theory(渾天說) results that the interplay between two Energy(氣) forces (yin and yang) affect the “great harmony” and “major actions” in all things in nature. Two theories proved that the world is created from the effect of the relationship between the energy and forces. According to the Sky Theory(渾天說) by Zhang-Zai(張載), the “great harmony between yin and yang,” expresses matters with the mechanism in which superfluous forms are generated in the Great Void(太虛) full of Energy. The Energy(氣) Flow in Taekwondo Training through Zhang-Zai(張載)’s Sky Theory(渾天說) shows the desire of the unification on all creations and mankind’s homing instinct to the beginning. It appears through Taekwondo Training, the state of energy shall maintain similar to when the existence of indistinguishable enery or force from the beginning of things.

Not just for adults! Evaluating the performance of multiple fish passage designs at low-head barriers for the upstream movement of juvenile and adult trout Salmo trutta

Longitudinal connectivity in salmonid streams is vital for juvenile as well as adult fish, yet most upstream passage studies consider only larger adults. Upstream passage of juvenile and adult brown trout Salmo trutta at low-head (<3m) structures on two River Ribble tributaries (NW England) was investigated using Passive Integrated Transponder (PIT) telemetry during summer-autumn 2013 and 2014. The efficiency of a Servais low-cost baffle (LCB) fish pass was evaluated for the first time, along with two pool-weir (PW) passes, an embedded rock ramp (ERR) and an open culvert (C), the latter a man-made structure within predicted swim speed, acting as an experimental control. We used a combination of naturally migrating trout and displacement experiments. Resident fish were displaced from above to below structures, utilising their homing instinct to instigate their ascent of the structure, with up to 91% of displaced trout attempting to pass. Approximately 30% of parr morphotype trout released at their capture locations attempted to pass upstream of structures in both streams. Passage efficiencies of up to 82% for the LCB pass design were similar to the PW (up to 79%) and better than the ERR (71%), but below that for C (96%–100%). Significant differences occurred between fish passes in time to passage, and number of attempts to pass, with all but PW1 having significantly longer time to passage than the control culvert. Median time to passage at PW2 decreased almost fifty fold between 2013 and 2014, following modification to equalise step heights at the structure. Logistic regression demonstrated a strong body-length effect on passage success at passes, with 50% probability of successful passage (82–132mm) varying, but not significantly, between passes. We conclude that small trout, including juveniles, can and do exhibit functionally significant upstream movement and that greater consideration should be given of their passage needs as well as for large, adult trout.

Conflict bear translocation: investigating population genetics and fate of bear translocation in Dachigam National Park, Jammu and Kashmir, India.

The Asiatic black bear population in Dachigam landscape, Jammu and Kashmir is well recognized as one of the highest density bear populations in India. Increasing incidences of bear-human interactions and the resultant retaliatory killings by locals have become a serious threat to the survivorship of black bears in the Dachigam landscape. The Department of Wildlife Protection in Jammu and Kashmir has been translocating bears involved in conflicts, henceforth ‘conflict bears’ from different sites in Dachigam landscape to Dachigam National Park as a flagship activity to mitigate conflicts. We undertook this study to investigate the population genetics and the fate of bear translocation in Dachigam National Park. We identified 109 unique genotypes in an area of ca. 650 km2 and observed bear population under panmixia that showed sound genetic variability. Molecular tracking of translocated bears revealed that mostly bears (7 out of 11 bears) returned to their capture sites, possibly due to homing instincts or habituation to the high quality food available in agricultural croplands and orchards, while only four bears remained in Dachigam National Park after translocation. Results indicated that translocation success was most likely to be season dependent as bears translocated during spring and late autumn returned to their capture sites, perhaps due to the scarcity of food inside Dachigam National Park while bears translocated in summer remained in Dachigam National Park due to availability of surplus food resources. Thus, the current management practices of translocating conflict bears, without taking into account spatio-temporal variability of food resources in Dachigam landscape seemed to be ineffective in mitigating conflicts on a long-term basis. However, the study highlighted the importance of molecular tracking of bears to understand their movement patterns and socio-biology in tough terrains like Dachigam landscape.

The homing instinct: meaning &amp; mystery in animal migration

The homing instinct: meaning &amp; mystery in animal migration

Site Fidelity: Rock Pigeons and Refugees

This paper presents a series of multi-disciplinary artworks developed from collaborations with local Tasmanian pigeon fanciers and homing associations. The artworks explore the desire to locate habitat in unstable environments, exposing bespoke ecosystems and visualising agency within a locational / relational feedback loop. The homing instinct of the rock pigeon is segued into the loss of home felt by local refugees. The wild rock pigeons' cohabitation with humans 10 000 years ago triggered a unique and mutually beneficial association, allowing safe shelter for bird and unprecedented carrier utility for human. The enduring relationship between bird and human has evolved in response to the pigeon's homing instinct, evidencing an empathetic bond driven by an urge to continually re-establish contact.Homing is an innate instinct to return to known territory via new and unknown environments. The contemporary bird / fancier relationship reveals layers of belonging, between animal, human and place. It more abstractly reflects a desire to be local; to belong within an emotional and spatial system, confronting and navigating tenuous places and experiences. Pigeon fanciers typically inhabit suburban environments, establishing the birds' lofts amongst the conglomerate nest of human habitation (sheds, carports, BBQ areas, clotheslines). From this domestic grotto, fanciers travel impressive distances to reach wilder places, releasing their birds to find their way back home. The bird's instinct of site fidelity sits counter to the fancier's instinct to reconnect to wild environs. It is a symbiotic relationship drawn from divergent urges.

Persistence of a southern Atlantic salmon population: diversity of natal origins from otolith elemental and Sr isotopic signatures

We investigated the use of Sr:Ca, Ba:Ca, and87Sr:86Sr ratios as natural tags for determining the natal origins of juvenile and adult Atlantic salmon (Salmo salar) from 12 tributaries in the Adour basin (southwestern France) and estimated homing on a tributary scale. Geochemical signatures from core regions of the otolith were also used to identify fish from hatchery or naturally spawned sources. Quadratic discriminant function analysis (QDFA) was on average 80% successful at classifying juveniles according to their natal rivers. Adults of unknown natal origin were assigned to their natal rivers using the juvenile fingerprints from QDFA approach. Only 18 adults originated from streams not included in the juvenile database. Although most of the adults showed a marked homing instinct, homing was not perfect, and some wild fish strayed into non-natal spawning areas. Returns of hatchery-reared fish as adult spawners represented 10% of the total sampled fish. Allocation of fish to natal tributaries or hatcheries illustrated the abundance and relative contributions of natal sources, important for the recovery of Atlantic salmon in this area.

지구 자기장 기반의 Fingerprint 실내 위치추정 방법 연구

기존의 전파에 의존한 실내 위치측위 시스템의 한계점 발생으로 실내환경에서 정확도 향상을 위한 새로운 방법의 도입이 필요한 시점이다. 최근 생태계 모방 기술이 미래의 핵심기술이 되었고, 이에 따라 귀소본능을 가진 동물들이 지구자기장을 탐색하여 생체자석으로 위치친지에 사용하는 점을 적용한 정확한 위치 측위 방법을 연구하였다. 실내 위치측위를 위한 새로운 자원인 지구자기장의 적용 가능성을 확인하기 위해 건물구조, 구성재료를 구분하고 실제 자기장센서를 탑재할 수 있는 구조물과 데이터수집 모듈을 설계한 뒤, Fingerprint 기법의 위치측위 시스템을 구성하여 위치측위 자원으로서의 지구자기장의 적용 가능성을 연구하였다. 위치측위 시스템 성능 평가에서 기존의 무선랜이 설치된 건물에서는 지구자기장 세기 기반의 위치측위 시스템이 무선랜 기반 위치측위 시스템과 유사하거나 약 20% 성능이 높이 나타났다. 이와같이 실내 위치측위를 위한 인프라 설치가 되어 있지 않는 환경에서는 지구자기장이라는 고유의 지구자원으로 실내 위치측위가 가능하다. Due to the limitations of the existing indoor positioning system depending on the radio wave, at present, it is required to introduce a new method in order to improve the accuracy in indoor environment. Recently, bio-inspired technology has become the future core technology. Thus, this study examined the accurate positioning method applying the abilities that animals with homing instinct measure their position by searching geomagnetic field with the use of their biomagnets. In order to confirm the applicability of geomagnetic field, a new source for indoor positioning, this study separated the constituent materials and building structure and designed the structures that can carry the actual magnetic field sensor and the data collection module. Subsequently, this study investigated the applicability of geomagnetic field as a positioning source by establishing the positioning system of Fingerprint method. In performance evaluation of the positioning system, the geomagnetic strength-based positioning system was similar to or approximately 20 percent higher than the wireless LAN-based positioning system in the buildings with the existing wireless LAN. Thus, in the environment without infrastructure for indoor positioning, the geomagnetic, an independent earth resource, can make it possible to realize the indoor positioning.

Tradeoffs between homing and habitat quality for spawning site selection by hatchery-origin Chinook salmon

Spawning site selection by female salmon is based on complex and poorly understood tradeoffs between the homing instinct and the availability of appropriate habitat for successful reproduction. Previous studies have shown that hatchery-origin Chinook salmon (Oncorhynchus tshawytscha) released from different acclimation sites return with varying degrees of fidelity to these areas. To investigate the possibility that homing fidelity is associated with aquatic habitat conditions, we quantified physical habitat throughout 165 km in the upper Yakima River basin (Washington, USA) and mapped redd and carcass locations from 2004 to 2008. Principal components analysis identified differences in substrate, cover, stream width, and gradient among reaches surrounding acclimation sites, and canonical correspondence analysis revealed that these differences in habitat characteristics were associated with spatial patterns of spawning (p < 0.01). These analyses indicated that female salmon may forego spawning near their acclimation area if the surrounding habitat is unsuitable. Evaluating the spatial context of acclimation areas in relation to surrounding habitat may provide essential information for effectively managing supplementation programs and prioritizing restoration actions.

(Mis)Reading the Libro de Buen Amor : Exemplary Ambiguity and Ambiguous Exempla

Ian Michael counts thirty-five popular tales in Libro de buen amor (LBA) calculating that they comprise more than twenty percent of entire text (177). (1) Regarding early works, Northrup Frye adds that [n]early every work of art in past had a social function in its own time, a function which was often not primarily an aesthetic function at (344) and adds that [o]ne of tasks of criticism is that of recovery of function, not of course restoration of an original function, which is out of question, but recreation of function in a new context (345). Given didactic intent of LBA, combined with its patent ambiguity, along with inherent polysemy of language of which Juan Ruiz was eminently aware (Read 240), his employment of anecdotes to impart life lessons with a salvific intent creates a literary tension begging resolution. This study examines exemplum of Ass and Lapdog not only by Juan Ruiz, but also by contemporaneous Libro del cauallero Zifar (Zifar; c. 1301), and later Esopete ystoriado (Esopete; 1488) to recover its social function to extent that these three witnesses permit and to recreate a function in a new context. Examining how this tale fits within frame text and observing differences between versions enable surmising what didactic functions of these versions may have been. Doing this permits viewing how Ruizian version includes a dimension lacking in other two, turning his version into a bawdy fabliau (Vasvari 13). In line with Frye's suggestion, a second appraisal of this tale from a postmodern view, specifically from a psychoanalytic one, however, offers another perspective which leads not only to the recreation of function in a new context, but also, perhaps, to a pleasure of text, not an original pleasure of a postlapsarian, medieval audience who heard or read story, but certainly to one of a postlapsarian, postmodern audience. When Terry Eagleton examines nature of in order to determine what is, he concludes that just as it will not do to see as an 'objective', descriptive category, neither will do to say that is just what people whimsically choose to call literature (16). Literature goes beyond private taste in that value judgments which determine are grounded in social ideologies by which certain groups maintain power over others (Eagleton 16). medieval Spanish anecdote examined here manifests a social ideology in which natural law held that [e]verything has its right place, its home, region that suits it, and, if not forcibly restrained, moves thither by a sort of homing instinct (Lewis 92). Aesopic tale known as The ass and lapdog--the source for Medieval fable examined here (Lecoy 114; Holmer 59; Vasvari 15) offers a fairly unambiguous moral, which to a twentieth-century audience, especially in land of free and home of brave where sky is limit, may not be as palatable as may have been to a Medieval audience with its particular Weltanschauung. Viewing tale through a psychoanalytic lens, however, allows unpalatable or at least less acceptable to become more so, and little valued to acquire greater value as well. fable, in itself uncomplicated, may be reduced to its bare essentials as follows: an ass sees a lapdog frolicking with its owner. Considering itself to be of greater utility than dog, ass too tries to frolic with its owner only to end up being rejected and beaten. accompanying moral in all three versions--Zifar, LBA, and Esopete--, in one way or another, alludes to idea that what pertains to one, may not pertain to another. People should keep their natural place. In LBA, however, fable and its moral acquire nuances that invite detailed consideration. Although Esopete's rendition has no frame within which to fit, too is fairly straightforward: 1) owner praises and prizes dog; 2) donkey denigrates dog calling pequeno and inmundo (38); 3) emphasis falls on donkey's considering itself better than dog: soy mejor que ella et para mas cosas e officios. …

Road Movie with an Extension of a Frame, Homing Instinct and Recovery - A Study on Jeon Soo-Il’s Films -

Road Movie with an Extension of a Frame, Homing Instinct and Recovery - A Study on Jeon Soo-Il’s Films -

Modelling and simulations of the migration of pelagic fish

Abstract Barbaro, A., Einarsson, B., Birnir, B., Sigurðsson, S., Valdimarsson, H., Pálsson, Ó. K., Sveinbjörnsson, S., and Sigurðsson, Þ. 2009. Modelling and simulations of the migration of pelagic fish. – ICES Journal of Marine Science, 66: 826–838. We applied an interacting particle model to the Icelandic capelin stock to reproduce the spawning migration route for three different years, successfully predicting the route for 2008. Using available temperature data and approximated currents, and without using artificial forcing terms or a homing instinct, our model was able to reproduce the observed migration routes from all 3 years. By a sensitivity analysis, we identified oceanic temperature and the balance between the influence of interaction among particles and the particles' response to temperature as the control parameters most significant in determining the migration route. One significant contribution of this paper is the inclusion of orders of magnitude more particles than similar models, which affects the global behaviour of the model by propagating information about surrounding temperature through the school more efficiently. To maintain the same dynamics between different simulations, we argue a linear relationship between the time-step, radii of interactions, and the spatial resolution, and we argue that these scale as N−1/2, where N is the number of particles.

Homing Devices in Choice of Tort Law: Australian, British, and Canadian Approaches

AbstractSince 1994, Canada, the United Kingdom and Australia have adopted new choice of law rules for cross-border torts that, in different ways, centre on the application of the law of the place where the tort occurred (thelex loci delicti). All three countries abandoned some species of the rule inPhillips v Eyre, which required some reference to the law of the forum (thelex fori) as well as thelex loci delicti. However, predictions were made that, where possible, courts in these countries would continue to show a strong inclination to apply thelex foriin cross-border tort cases—and would use a range of homing devices to do so. A comprehensive survey and analysis of the cases that have been decided under the Australian, British and Canadianlex loci delictiregimes suggests that courts in these countries do betray a homing instinct, but one that has actually been tightly restrained by appeal courts. Where application of thelex foriwas formally allowed by use of a ‘flexible exception’ in Canada and the United Kingdom, this has been contained by courts of first appeal. Indeed, only the continuing characterization of the assessment of damages as a procedural question in Canada and the United Kingdom, seems to remain as a significant homing device for courts in these countries.

Migration and survival of farmed Atlantic salmon (Salmo salar L.) released from two Norwegian fish farms

Abstract Many salmon escape from fish farms during autumn and winter, making the migratory pattern and survival to sexual maturity of these fish an interesting topic of study. This study aimed to assess the migration and survival of large farmed salmon released from fish farms at different times during autumn and winter. Farmed salmon were individually tagged with external tags and released from two fish farms, one in southern Norway and the other in northern Norway. Salmon released in autumn one year before attaining sexual maturity appeared to survive poorly to sexual maturation, whereas salmon escaping later in winter showed greater survival. The released salmon appeared to move with the current and appeared to have a very weak homing instinct, if any. Based on the results of the tagging experiments, the direction and speed of ocean currents, and information about the abundance of fish farm escapees in salmon fisheries and stocks in several countries in the Northeast Atlantic, two hypotheses are advanced: first, salmon that escape during early autumn the year before they become sexually mature are transported with the currents to Arctic areas and subsequently do not survive the winter; second, large salmon escaping from fish farms in Ireland, Scotland, the Faroe Islands, and Norway during winter and spring move with the current and, during the following summer or autumn, may enter homewater fisheries and spawning populations far away from the site of escape, when they become sexually mature.

Fish and stream habitat risks from uncharacteristic wildfire: Observations from 17 years of fire-related disturbances on the Boise National Forest, Idaho

Several large, uncharacteristic wildfires occurred on the Boise National Forest in Southwest Idaho, from 1986 to 2003. From 1987 to 1994, severe wildfires burned almost 50% of the ponderosa pine forest types (about 200,000 ha). The intensity of the fires varied across the landscape, with a mix of low to moderate severity, and lesser amounts of high burn severity. After the fires, localized debris flows favored smaller order streams in watersheds less than 4000 ha in size, where there had been mostly high severity burning. Locally, areas experiencing high heat and post-fire debris flows had reduced fish numbers and altered fish habitats. Uncharacteristic wildfires on the managed portions of the Boise National Forest appeared to have more pronounced, short-term effects on fish habitats as compared with characteristic wildfires in the Central Idaho Wilderness. Even in the most severely impacted streams, habitat conditions and trout populations improved dramatically within 5–10 years. Post-fire floods apparently rejuvenated stream habitats by exporting fine sediments and by importing large amounts of gravel, cobble, woody debris, and nutrients, resulting in higher fish productivities than before the fire. These observations suggest that important elements of biodiversity and fish productivity may be influenced, or even created by fire-related disturbances. In some cases, habitats that were completely devoid of salmonid fishes just after the debris floods, were later re-colonized with migrants returning from downstream or nearby tributary rearing habitats. Re-population was likely enhanced by higher fecundity, homing instinct, and greater mobility of the larger migratory fish. Ecosystem restoration activities that reduce both short- and long-term threats of uncharacteristic wildfire on imperiled fishes could be emphasized in areas where local populations may be weak and/or isolated, but potentially recoverable. But forest ecosystem restoration alone may not reduce risks to fish if existing habitat conditions and isolation are limiting the population.