Resident Individuals Research Articles

Health Assessments of Koalas after Wildfire: A Temporal Comparison of Rehabilitated and Non-Rescued Resident Individuals.

Many koalas (Phascolarctos cinereus) required rehabilitation after the 2019/20 Australian megafires. Little is known about how the post-release health of rehabilitated koalas compares to non-rescued resident koalas. We evaluated health parameters in rehabilitated koalas and resident koalas in burnt and unburnt habitat in southern New South Wales, Australia. Health checks were undertaken within six weeks of fire (rehabilitated group), 5-9 months post-fire and 12-16 months post-fire. Body condition improved significantly over time in rehabilitated koalas, with similar condition between all groups at 12-16 months. Rehabilitated koalas therefore gained body condition at similar rates to koalas who remained and survived in the wild. The prevalence of Chlamydia pecorum was also similar between groups and timepoints, suggesting wildfire and rehabilitation did not exacerbate disease in this population. While there was some variation in measured serum biochemistry and haematology parameters between groups and timepoints, most were within normal reference ranges. Our findings show that koalas were generally healthy at the time of release and when recaptured nine months later. Landscapes in the Monaro region exhibiting a mosaic of burn severity can support koalas, and rehabilitated koala health is not compromised by returning them to burnt habitats 4-6 months post-fire.

Drivers of partial migration in the reddish egret Egretta rufescens

The reddish egret Egretta rufescens is North America's rarest Ardeidae and is listed as ‘Near Threatened' by the IUCN, as endangered in Mexico, and as a species of conservation concern throughout much of its range in the United States. Little is known about the migratory behavior of the reddish egret. Individuals that were banded during the breeding season in Texas, USA, have been resighted away from breeding areas; however, records are limited and the extent of migration is unknown. Using GPS transmitters, we found reddish egrets breeding in southern Texas exhibited a partial migration strategy, with 39% of the marked population migrating from breeding sites. We assessed the dominance, body size, and arrival time hypotheses to better understand the drivers of partial migration. We did not find support for the body size hypothesis and found mixed support for the dominance hypothesis; both males and females migrated, and migratory status of individuals did not change across the years of study. Long‐distance migrants were also larger than resident individuals. We found some support for the arrival time hypothesis; residents began breeding earlier than long‐distance migrants and had moderately greater nest success. However, within long‐distance migrants, an earlier arrival to breeding areas did not necessarily equate to earlier nesting or greater nest success. This study is the first to examine the migratory behavior of adult reddish egrets and assesses the dominance, body size, and arrival time hypotheses as explanations for partial migration in this species. Further, the results of this study emphasize the need for international conservation efforts.

RESIDENTS AND NON-RESIDENTS: DAILY ACTIVITY OF SMALL MAMMALS IN CONTRASTING BIOTOPES

Using the marking and recapture method, we compared the daily activity of four common species of small mammals of the forest zone in three biotopes that differ greatly in their protective properties. Lines of live traps were installed in a dark coniferous forest, on a grassy slope and along a rocky beach along the water's edge on the river. Ilych. The activity of resident and non-resident individuals was assessed with a frequency of checks every 1.5 hours. In the forest, polyphasic activity without pronounced maxima was noted for all species; on the open slope, the maximum activity of resident animals occurred at night, and on the shore only non-resident animals were observed. Non-resident activity in all biotopes is shifted to the night, while in open biotopes the period of activity is shorter and more associated with the dark time of day.

High risk, high reward? Influence of experience level in the selection or avoidance of artificial feeding sites by Eurasian lynx

Artificial feeding of wildlife is a widespread, but controversial, management practice with many positive and negative effects. Besides the effects on the target species, it can also affect other (non-target) species by modulating interspecific interactions. Previous research showed that the presence of artificial feeding sites for bears and ungulates increases the risk of kleptoparasitism by the brown bear (Ursus arctos) on kills made by Eurasian lynx (Lynx lynx). However, it remains unknown whether lynx adjust their behaviour to the distribution of artificial feeding sites, which also attract potential prey (ungulates) for lynx. Using GPS telemetry data, we explored the spatiotemporal lynx response to such sites and studied how this response varied with experience level, i.e. between adult resident individuals ('experienced lynx') and juveniles and/or translocated individuals ('naïve lynx'). We found that lynx experience played an important role in the use of artificial feeding sites. Specifically, while both experienced and naïve lynx selected feeding sites while moving within their home range, the attraction was stronger among the naïve lynx. Considering the distribution of kill sites, naïve lynx killed prey closer to the artificial feeding sites than expected, while experienced lynx avoided them. Finally, the proximity to artificial feeding sites by experienced lynx showed an annual variation, matching the seasonal kleptoparasitism risk, with overall closer proximity to feeding sites during the winter, when bears are less active, which is also when ungulates are more concentrated around feeding sites. Our study suggests that, despite the relatively recent introduction of artificial feeding in the ecosystems, wildlife can learn to respond to the altered interactions with other species. However, this appears to be a learning process with manifold management and conservation implications. A better understanding of species interactions and space use in the context of resource manipulation is increasingly relevant as the use of anthropogenic food by wildlife is nowadays substantial and widespread across most parts of the world.

Migrant orangutan males use social learning to adapt to new habitat after dispersal

Dispersal has been suggested to be challenging, especially for species that heavily rely on social learning for knowledge acquisition. One of the obstacles that migrants face is learning how to cope with an unfamiliar, new habitat, which may involve learning from resident individuals. So far, only very few studies have looked at social learning in migrants after dispersal. Here we examine how migrant male orangutans use a behavior called “peering” (an indicator of observational social learning), to learn from local individuals. In total, we analyzed 4,009 daily dyadic associations with and without peering events of 77 males of the highly sociable Sumatran orangutans (Pongo abelii) at the Suaq population and 75 males of the less sociable Bornean orangutans (Pongo pygmaeus wurmbii) at the Tuanan population, covering a combined study time of 30 years. Analysis using generalized linear mixed models supported our prediction that migrant males in Suaq preferentially peered at the local adult females. However, in Tuanan, migrants peered mostly at other adult males and local immatures. Migrants’ peering rates were highest shortly after their arrival, and significantly decreased with increasing time spent in the area. Migrants in both sites peered significantly more at peering targets’ feeding on food items that are rarely eaten within the locals’ diet, than at commonly eaten ones and peered significantly more at skill-intense food items than easy-to-process ones. Further, migrants interacted significantly more with the peered-at food item after the peering event, than before, suggesting that they practice the observed behavior. Our results therefore suggest that migrant males use peering to learn new ecological knowledge after dispersal (e.g., where and what to feed on), and continue to learn complex skills even within adulthood, (e.g., how to feed on skill-intense food items). To do so, migrants selectively attend to the most knowledgeable and/or available individuals, practice the new skill afterwards and even flexibly adjust their learning, e.g., when confronted with intolerant locals or when the need for learning decreases. Together, our study provides important evidence that social learning in great apes expands towards adulthood, an ability which critically impacted also human evolution.

Should I Stay or Should I Go? Seasonal Fluctuations of Wood Mouse Populations in Fields Surrounded by Woodlands.

The wood mouse Apodemus sylvaticus is common in woodlands and open areas of the Western Palearctic. Despite extensive research, little is known about its population ecology in fields in the Mediterranean area, where the climate involves great seasonal changes in environmental features. Here, we investigated wood mice seasonal fluctuations in the number of captures and population structure by sampling long-fallow fields and woodlands, i.e., oak forest and conifer plantation, in a heterogeneous landscape of central Italy. Mice were live-trapped every two months for three years (23.814 trap-days). The number of captures, mice body weight, and proportion of adult, residents and breeding individuals were analyzed. Mice dynamics changed across seasons and habitats. In fields, we recorded more captures, more reproductive individuals, and fewer non-adults and resident individuals in the warmer months compared to the colder months; mice were heavier in warmer months. During the cold season, the captures and adult proportion in fields were lower than in resource-rich woodlands. Breeding and non-resident mice were more abundant in fields than in woodlands in warmer months. Overall, the seasonal demographic variations we recorded provide evidence that fields can represent a suboptimal habitat in Mediterranean heterogeneous landscapes, acting nonetheless as a source of food resources, cover, and mates for mice in spring-summer.

Provisioning ecotourism does not increase tiger shark site fidelity

A perennial criticism of provisioning ecotourism is that it alters the natural behavior and ecology of the target species by providing an artificial food source. Here we evaluate its impact on the long-term site fidelity patterns of tiger sharks in French Polynesia. We hypothesized that a significant impact of provisioning would lead to (1) increases in individual site fidelity over time, and (2) an increase in the number of resident individuals over time. Of 53 individuals photo-identified and monitored during > 500 dives over five years, 10 individuals accounted for > 75% of all sightings, whereas 35 sharks were sighted very infrequently. Even the most frequently observed tiger sharks exhibited overall low fidelity at the site and showed no increase in site fidelity over time. Furthermore, the number of tiger sharks sighted during each dive did not increase. The observed patterns of tiger shark sightings were best explained by natural movements, including general roaming within home ranges along the coastline and seasonal migrations. Despite the apparent lack of impact of provisioning ecotourism on tiger shark ecology in Tahitian waters, it would be prudent to implement a strict code of conduct during any future provisioning activities to maximize the safety of participants and animals involved.

Factors Influencing Prevalence and Intensity of Haemosporidian Infection in American Kestrels in the Nonbreeding Season on the Baja California Peninsula, Mexico

ABSTRACT Overwintering areas can act as reservoirs for haemosporidians, and their blood-sucking vectors may easily survive and flourish in warm climates. The American Kestrel (Falco sparverius) is a small-sized raptor that includes both resident and migratory individuals that overwinter in agriculture areas of the Baja California peninsula, Mexico. We measured and collected blood samples from 54 individual kestrels captured in a fragmented habitat located within a matrix of agricultural and native scrub in the southern part of the peninsula during the autumn and winter of 2018–2019 and 2019–2020. We identified and quantified haemosporidians in blood smears of each individual. We used decision tree classification models of prevalence and intensities of haemosporidians to assess the importance of season, host body size, and environmental characteristics of the capture site (proximity to the nearest infected host, number of ponds used for irrigation, Normalized Difference Vegetation Index [NDVI], distance to the edge of the agricultural matrix, and distance to the nearest city). Overall prevalence was 42.6%, with an average intensity of 2.4 haemosporidian-infected cells per 2000 erythrocytes. Most haemosporidians (91.3%) were identified as Haemoproteus tinnunculi, and the rest as Plasmodium spp. The prevalence of haemosporidians increased with pond availability, the distance from the edge of the agricultural matrix, and the proximity of infected individuals. Parasite intensity increased with the availability of ponds, the distance to the edge of the agriculture matrix, and the NDVI. Spatial and temporal patterns of parasite prevalence and intensity illustrated local infection dynamics, suggesting a complex scenario of haemosporidian transmission in migratory and resident kestrels.

Description and quantification of micronucleus and nuclear abnormalities in erythrocytes of the sentinel green turtle (Chelonia mydas) with fluorescence microscopy.

Contamination in marine ecosystems is of the most critical threats to marine turtles. The identification of useful biomarkers to detect and monitor the physiological and clinical effects of pollutants on these populations will allow early detection of alterations (e.g., mutagenic damages) that could risk their viability or favor the development of diseases, thus threatening the biodiversity of these ecosystems and human population. This study is aimed at describing and quantifying nuclear anomalies in peripheral blood erythrocytes of green turtles (Chelonia mydas) from three distinct foraging areas in Mexico (Akumal, Xcalak, and Punta Herrero). We developed a novel morphological index that could be used as a biomarker to identify abnormal nuclei in peripheral blood erythrocytes. Here we describe for the first time in C. mydas, with a species-specific staining protocol, distinct nuclear abnormalities such as blebbed, lobed, notched, eight shape nuclei, and binucleated cells. These nuclear abnormalities were present in >90 % of the subjects (n=30). Moreover, 50 % of the organisms presented erythrocytes with micronuclei. The number of nuclear abnormalities did not correlate with size of the green turtles or differ between sites, or health status. We found a higher frequency of green turtles with nuclear abnormalities in the southern region (Punta Herrero and Xcalak) with the highest frequency of micronucleus and buds. The former could be associated to the constant exposure to chemical pollutants of oceanographic origin in the southern coast of Quintana Roo. Furthermore, the increasing anthropogenic pollution in Akumal could also explain the highest variability in the number of nuclear abnormalities presented in resident individuals. We propose that a long-term monitoring programs of green turtle populations in the Mexican Caribbean that include a micronucleus test could be a useful to determine possible mutagenic damage in these animals.

About Currency Restrictions in 2022, Introduced in Respect of Individuals

The focus of this article is the currency restrictions imposed by the Russian Federation on resident individuals in response to the deployment by foreign states and their unions of a policy of sanctions pressure on the national banking system. First, the authors identify regulatory windows and types of country sanctions: freezing of reserves and assets of the Bank of Russia, a ban for the Bank of Russia on access to the capital market and a ban on the sale, supply, transfer or export of cash euros and US dollars to Russia. Further, the domestic legal order is analyzed in terms of the introduction and operation of currency restrictions that apply to resident individuals. It is revealed that the main restrictions consisted in the forced conversion of part of foreign currency deposits, prohibitions on crediting currency to foreign accounts and providing loans to non-residents, setting thresholds for crossborder transfer of non-cash and cash funds; prohibition of electronic money transfers with the help of foreign payment service providers and transactions with persons of foreign states committing unfriendly acts or included in the sanctions list by the Government of the Russian Federation. The legality of the establishment of these currency restrictions and the practice of their application are investigated. Based on the results of the analysis, ways to improve domestic legislation are proposed.

A note on site fidelity of marine tucuxis (Sotalia fluviatilis) in Guanabara Bay, southeastern Brazil

Since 1995, photo-identification techniques have been used to study the marine tucuxis (Sotalia fluviatilis) found in Guanabara Bay (22°50’S, 43°10’W), southeastern Brazil. The bay is surrounded by a metropolitan complex and is the most degraded area of this species’ distribution. From May 1995 to June 2003, 47 photo-identification boat surveys were conducted in the bay. Sixty-nine individuals were identified and catalogued. The results indicate that individual tucuxis have high site fidelity in Guanabara Bay. On average, dolphins were seen for 4.5 consecutive years, with a range of 1 to 8 years. Additionally, calves have remained in the area beyond sexual maturity. Guanabara Bay provides food and breeding grounds for this dolphin population, despite its high degree of degradation. The fact that such a small dolphin population, composed of resident individuals, depends on such a degraded area may pose serious problems for its conservation.

Seasonal abundance and distribution patterns of common bottlenose dolphins (Tursiops truncatus) near St. Joseph Bay, Florida, USA

Three unusual mortalities events involving bottlenose dolphins (Tursiops truncatus Montagu 1821) occurred along Florida’s northern Gulf of Mexico coast between 1999 and 2006. The causes of these events, in which over 300 bottlenose dolphins are known to have died, are still under investigation. The impact of these mortality events cannot be fully evaluated, because little prior information on bottlenose dolphin abundance and distribution patterns exist in this region. Thus, the goals of this study were to estimate seasonal abundance, develop site-fidelity indices, and describe distribution patterns of bottlenose dolphins in St. Joseph Bay, Gulf County, Florida, USA. This study site was chosen because it was impacted by all three unusual mortality events and was the geographic focus of the 2004 event. Mark-recapture photo-identification surveys were conducted across multiple seasons from February 2005 through July 2007. Site-fidelity indices were calculated for each identifiable dolphin based upon all photo-ID efforts undertaken in the area. Distribution patterns were investigated by short-term (12-94 days) radio-tracking of tagged individuals across seasons (April-July, n=9; July-October, n=15). Mark-recapture closed and robust abundance estimates, as well as site-fidelity indices suggest that St. Joseph Bay supports a resident community of 78-152 bottlenose dolphins. During spring and autumn, this region experiences an influx of dolphins, as demonstrated by closed and robust abundance estimates of 313-410 and 237-340, respectively. These results are supported by the distribution patterns of radio-tagged individuals. Individuals tagged in summer tended to stay within or near St. Joseph Bay, whereas two individuals tagged in spring ranged more than 40km from the study site. This study provides the first detailed examination of bottlenose dolphin abundance and distribution patterns for this region of the northern Gulf coast of Florida. These results suggest that unusual mortality events probably had, and will in the future have, seasonally variable effects on bottlenose dolphins in St. Joseph Bay. Future mortality events that occur during the summer and winter in St. Joseph Bay may predominantly affect resident individuals, while those that occur during the spring and autumn will probably affect both residents and seasonal visitors.

Implementation and effectiveness of a linkage to HIV care intervention in rural South Africa (ANRS 12249 TasP trial).

Timely linkage to care and ART initiation is critical to decrease the risks of HIV-related morbidity, mortality and HIV transmission, but is often challenging. We report on the implementation and effectiveness of a linkage-to-care intervention in rural KwaZulu-Natal, South Africa. In the ANRS 12249 TasP trial on Universal Testing and Treatment (UTT) implemented between 2012-2016, resident individuals ≥16 years were offered home-based HIV testing every six months. Those ascertained to be HIV-positive were referred to trial clinics. Starting May 2013, a linkage-to-care intervention was implemented in both trial arms, consisting of tracking through phone calls and/or home visits to "re-refer" people who had not linked to care to trial clinics within three months of the first home-based referral. Fidelity in implementing the planned intervention was described using Kaplan-Meier estimation to compute conditional probabilities of being tracked and of being re-referred by the linkage-to-care team. Effect of the intervention on time to linkage-to-care was analysed using a Cox regression model censored for death, migration, and end of data follow-up. Among the 2,837 individuals (73.7% female) included in the analysis, 904 (32%) were tracked at least once, and 573 of them (63.4%) were re-referred. Probabilities of being re-referred was 17% within six months of first referral and 31% within twelve months. Compared to individuals not re-referred by the intervention, linkage-to-care was significantly higher among those with at least one re-referral through phone call (adjusted hazard ratio [aHR] = 1.82; 95% confidence interval [95% CI] = 1.47-2.25), and among those with re-referral through both phone call and home visit (aHR = 3.94; 95% CI = 2.07-7.48). Phone calls and home visits following HIV testing were challenging to implement, but appeared effective in improving linkage-to-care amongst those receiving the intervention. Such patient-centred strategies should be part of UTT programs to achieve the UNAIDS 95-95-95 targets.

Natural Selection at the Edge of Life: Allelic Polymorphism and Recruitment in High Latitude Arctic Char (Salvelinus alpinus) Generated and Maintained by Environmental Extremes

Information from extreme habitats of polymorphic populations is expected to answer questions related to evolutionary changes occurring at their niche border. Landlocked and resident/anadromous populations of the Arctic char (Salvelinus alpinus (L.) sp. complex), sampled during three successive years in northern Svalbard, were assessed for life-history characteristics, allele-frequency variation at the polymorphic EST-2* locus, and tested for genotype–environment interactions. While year-class strength correlated positively with mean air temperature during the two summers preceding spawning, the EST-2*100 allele frequency correlated positively with the air temperature in June after birth. By affecting two asynchronous and independent population variables, which are both no doubt correlated with fitness, annual temperature variation is suggested to generate and maintain polymorphism in Arctic char in the High Arctic by modifying year-class strength and selecting for variant alleles influencing cold resistance. Intra- and inter-population comparisons imply an additional selection between the two variant EST-2* alleles to operate ontogenetically, with a fixation on the 90 allele in landlocked and resident individuals and the 100 allele in anadromous individuals. The selective mechanism behind the latter processes is unknown. Because of low substrate specificity, however, esterases may form a reserve of adaptive ability towards environmental stress during contrasting conditions.

Environmental DNA as a detection tool for small-bodied, cryptic, threatened fish in a highly turbid freshwater lake system

Context Where conservation efforts are undertaken to decrease downward trends in fish populations, comparatively few resources are directed to small-bodied cryptic species. The true extent of the decline of many of these species is therefore often unknown. Where surveys have occurred, they are frequently limited by budget and hence effort. Consequently, there is a risk that rare species may not be physically captured despite their presence at a site. Such an outcome has dire consequences for the conservation of remnant populations of threatened fish. To counter possible false negative detections, environmental DNA is increasingly being used in conjunction with, or as a precursor to, physical surveys. The Southern Purple-spotted Gudgeon (Mogurnda adspersa) is a small, threatened freshwater fish native to Australia. Recent surveys captured M. adspersa in two highly turbid waterbodies in north-central Victoria. This capture represented the first detection of the species in the state in more than 20 years. Because these waterbodies are part of a network of hydrologically connected systems, it was suspected that the species likely had a broader distribution in the region. Aims To develop a probe-based eDNA assay for M. adspersa and compare its sensitivity against a physical sampling program. Methods Detection (presence/absence) between eDNA and traditional surveys was compared across multiple sites. Key results eDNA presents an effective tool for determining the presence of M. adspersa. The eDNA survey demonstrated significant clustering of eDNA detections towards the outlets of lakes sampled, suggesting concentrated eDNA at this point, or that, due to the channels being shallower, the eDNA of resident individuals may be less diluted. Conclusions Based on these results, future survey of rare, cryptic species in highly turbid lake systems should in the first instance include a broad scale eDNA survey, with sampling concentrated at outlet channels. Implications The likely most cost-effective approach to determining the presence/absence of rare species in lake systems is the collection of eDNA samples at outlet channels.

Patterns in spatial use and movement of Silver Carp among tributaries and main-stem rivers: insight from otolith microchemistry analysis

Invasive Silver Carp (Hypophthalmichthys molitrix) have established populations throughout the Missouri River basin. The main-stem Missouri River has undergone a multitude of alterations, creating a channel with greater mean depths and velocities, limiting optimal habitat for Silver Carp. Tributaries to the Missouri River may provide refuge from the swift flows within the main-stem Missouri River and, therefore, may play a vital role in the life-cycle of Silver Carp throughout the basin. Understanding the spatial extent under which these invasive fish function in this large, open river system is crucial to inform management efforts. Here, we used otolith microchemistry of Silver Carp from the Kansas River, a major tributary to the Missouri River, to reconstruct environmental histories as a means to assess the proportions of resident (individuals who never left the Kansas River system) and transient (individuals who at some point occupied the Missouri River) individuals. Silver Carp within the Kansas River were predominantly residents (adults = 54%; juveniles = 65%) with the majority of reproduction coming from within the Kansas River itself. These results suggest removal efforts in the Kansas River may be effective means of managing this invasive fish species. Transient fish exhibited short durations of signatures indicative of the Missouri River (mean percent of data points for adults = 10% and juveniles = 36%), suggesting movements into the Missouri River were brief. These results highlight the importance of connectivity of tributary habitat among large rivers and provides important information for invasive species management.

Resident jaguars (Panthera onca) at the heart of the Maya Forest in Guatemala

In this study we determined the resident status of individual jaguars (Panthera onca) in a 7-year timeframe, in order to provide insight into the life history of this species as an input for abundance estimations and the management of the Maya Forest shared by Guatemala, Mexico, and Belize. We gathered photographic jaguar records from studies conducted in 2 Core Zones of the Maya Biosphere Reserve from 2013 to 2019. Individual jaguars were identified by their unique coat pattern, and were considered as residents when recorded for 3 or more consecutive years. Also, range sharing and interactions were quantified. Both female and male resident individuals were recorded. We suggest the presence of a resident population with a tendency for spatial or temporal range exclusion within individuals from the same sex and a fast male’s turnover, and a demographically mixed group of transients. These circumstances appoint the relevance to determine the resident status of individuals for accurate abundance estimations and population trends, and also in maintaining the integrity of the transboundary continuous forest cover, as connectivity appears to have an important role for maintaining the fluctuating jaguar population dynamics.

What's the effectiveness of stocking actions in small creeks? The role of water discharge behind hatchery trout downstream movement.

Fish stocking to enhance freshwater fisheries or to improve the conservation status of endangered fish species is a common practice in many countries. Little is known, however, of the effectiveness of these practices in spite of the high efforts and investments required. The movement of subadult/adult hatchery-released brown trout Salmo trutta L. was studied by passive telemetry in a small tributary of Lake Lugano (i.e., Laveggio Creek, Canton Ticino, Switzerland). Hatchery fish, together with some resident wild individuals sampled during electrofishing surveys, were tagged with Passive Integrated Transponders (PIT) tags. Hatchery fish were released upstream and downstream a submersible monitoring antenna, which was anchored to the streambed in a pass-over orientation. The number of hatchery fish detected daily by the antenna (divided between fish released upstream and downstream the antenna) was analyzed in relation to the daily water discharge, to search for similar patterns in their fluctuation over time. Only the movement of fish released upstream the antenna displayed a significant relationship with water discharge, with the highest number of fish detected during periods of high-water flow, occurring after heavy rains. High-water discharge events had a significant role in hatchery trout downstream movement in our study site, likely acting as a driver for the downstream migration to Lake Lugano. Such events contributed to the poor effectiveness of stocking actions in this small tributary, providing further evidence against stocking strategies based on subadult/adult fish.

Comparing morphological, parasitological, and genetic traits of an invasive minnow between intermittent and perennial stream reaches

Abstract Invasive fishes are a major environmental issue at the global scale, particularly for their impacts on freshwater ecosystems via the mechanisms of hybridisation, competition, predation, and disease transmission. This is of special conservation concern on the Iberian Peninsula due to the high level of endemism. With the aim to improve our knowledge on the invasion process of non‐native fishes, the present study consists of analysing key biological traits potentially related to their colonisation capacity: morphology, parasite communities, and genetic diversity. A non‐native population of Languedoc minnow Phoxinus septimaniae (leuciscid species native to south‐east France) was assessed in Tordera Stream (north‐eastern Iberian Peninsula). Fish were sampled in mid‐May (reproductive period) 2018 and 2019. Biological traits were compared between colonising and resident individuals from stream reaches of intermittent and perennial flow, respectively. After adjusting for fish size/body mass with analysis of covariance, body condition and health status (external and internal examination) tended to be better in the intermittent reach. Parasite load (number) and diversity (Shannon index) were significantly higher in the perennial reach. Fish development was also more stable in colonising minnow, as detected by low levels of fluctuating asymmetry for the eye diameter and the length of pectoral fins (adjusted for bilateral character size). Genetic diversity (microsatellite markers) was lower in resident minnow. Minnow genetic homozygosity (index of internal relatedness) was positively associated with parasite load and developmental instability (high fluctuating asymmetry levels). Our results show that colonising minnows display particular profiles of morphological, parasitological, and genetic traits that apparently allow these individuals to increase their dispersal capacity to survive and reproduce in harsher environmental conditions. The potential mechanisms may be related to a wider physiological tolerance, better immune response, parasite resistance/tolerance, and genetic diversity in colonising specimens. Such information reveals the specific traits of successful fish invaders under a seasonal colonisation dynamic. These data are relevant for environmental managers, to predict and identify areas vulnerable to invasion, in order to establish monitoring programmes for early detection, which will help to reduce the spread of non‐native fish populations.

Personal Income Tax Law Changes and the Impact on Family Budget in Albania

Personal income tax is a tax on wages or salaries and other income a person earns during a calendar year. It is calculated on the income of all resident individuals and each government imposes personal income tax on earnings according to its fiscal package. The taxable incomes has been on focus of the latest fiscal package of Albanian Government approved by the end of December 2019 and starting from January 2020, changes effect a larger category of people. This paper is focused in analyzing the changes of personal income tax law and evaluating the impact on family budget. Considering the effects in the standard of living, this evaluation will show the need for other regulations. Interesting implications will be explored for policy makers and working persons in Albania.