Feeding Areas Research Articles

ХИМИКО-ТЕХНОЛОГИЧЕСКИЕ ОСОБЕННОСТИ СУСЛА И ВИНА ИЗ НОВЫХ ГИБРИДОВ И СОРТОВ ВИНОГРАДА СЕЛЕКЦИИ АЗОСВиВ

The influence of the characteristics of new varieties and hybrids based on Krasnostop Anapskiy variety on the quality of grapes and chemical and technological parameters, and taste characteristics of wine products was studied in the experiment. The author in the article presents research materials on must and dry wine materials from hybrid varieties and forms of crossed pairs of grapes (F/U ‘Dzhemete’ x Krasnostop Anapskiy) bred at the Anapa Zonal Experimental Station of Viticulture and Wine-making. All new varieties and hybrid forms of a technical direction, average term of maturing. Productivity is high, they are tolerant to phylloxera. The must and wine material from the Krasnostop Anapskiy variety was used as a control. Place of laying the experiment is Anapa, Krasnodar region, Anapa ampelographic collection. Pruning of vineyards is «Spiral cordon AZOS-1». The feeding area is 3.5 x 2.0 m. As a result of the analysis of fresh grapes from the studied varieties and hybrids, it was revealed that all the studied varieties and hybrids, with the exception of the 59-60 form, accumulated a fairly high amount of sugars – 19.9-22.9 g/100 cm3 . The must of Krasnostop AZOS and Kubanets varieties and 59-24 form had a concentration of phenolic compounds significantly higher than the control. The most optimal in terms of glucoacidometric index was the mustof the control variety Krasnostop Anapskiy and 59-49 and 59-24 forms. The wine materials of most of the studied varieties and hybrids were not inferior to the control in terms of alcohol concentration. The highest concentration of substances of the polyphenol group was found in wines from the hybrid 59-24 and from the Krasnostop AZOS and Kubanets varieties. Coloring anthocyanin substances in the highest concentration were found in the studied wine materials from hybrid grapes 59-24 and 59-60, as well as from the Krasnostop AZOS variety. The tasting analysis showed that the wines from the studied hybrids and varieties are not inferior or superior in organoleptic parameters to the control variety Krasnostop Anapskiy.

Trophic assessment of three sympatric batoid species in the Southern Gulf of California.

The competitive exclusion principle establishes that the coexistence of closely related species requires a certain degree of resource partitioning. However, populations have individuals with different morphological or behavioral traits (e.g., maturity stages, sexes, temporal or spatial segregation). This interaction often results in a multi-level differentiation in food preferences and habits. We explored such resource partitioning between and within three batoid species: Hypanus dipterurus, Narcine entemedor, and Rhinoptera steindachneri in the southern Gulf of California, Mexico, using a combination of stomach content (excluding R. steindachneri) and stable isotope analyses. We found a clear differentiation between H. dipterurus and N. entemedor, where the latter exhibited more benthic habitats, supported by a greater association to infaunal prey and higher δ13C values. Though the degree and patterns of intra-specific segregation varied among species, there was a notable differentiation in both sex and stage of maturity, corresponding to changes in specialization (i.e., isotopic niche breadth) or trophic spectrum (varying prey importance and isotopic values per group). This work is a promising step towards understanding the dietary niche dynamics of these species in a potentially important feeding area within the southern Gulf of California, as well as the biological and ecological mechanisms that facilitate their coexistence.

Red squirrel Sciurus vulgaris abundance in coastal cliffs in the South of Spain

We studied the abundance of red squirrels, a medium-sized forest rodent widely distributed throughout the Palearctic, in the cliffs of Maro-Cerro Gordo (south of Spain, Málaga-Granada), a protected area with a great marine influence. We investigated the abundance of squirrels in this area in relation to two scales: (1) home range, as signs per square meter; and (2) landscape, as active nests per 1 x 1 km UTM grids. We tested the influence of land use and habitat features on the abundance of squirrels. On the home range scale, squirrel activity was higher in mature pines located near cliffs and in pines near freshwater channels. The cliffs hosted the best pine forest patches, and despite being very close to the sea, squirrels often used these as feeding areas but not as areas for building nests. On the landscape scale, squirrel nests were rarer in grids with more herbaceous crops and were more abundant in grids with longer freshwater streams. These results suggest that the squirrels in this area may have adapted to life at this site and to the marine influence via a differential use of habitat. The squirrels' use of the best feeding areas suggests saline stress is counteracted by establishing nests in humid areas away from cliffs.

Isotopic niches of juvenile and adult green turtles (Chelonia mydas) in feeding and nesting areas in Brazil, southwestern Atlantic Ocean

Stable isotope analysis is an approach that allows inferring feeding ecology and trophic structure of populations, especially for species that are difficult to observe in natural habitats, such as marine turtles. This study investigated the niche breadth of adult and juvenile green sea turtles (Chelonia mydas) through δ15N and δ13C values in carapace scutes. During 2017 and 2018, tissues were collected from juveniles in a feeding area in southeastern Brazil (n = 60) and from adults in a nesting area in northeastern Brazil, at Fernando de Noronha (n = 21). Our results revealed no temporal variations in the isotopic values of adult green turtles and the mean δ15N values are compatible with the isotopic values of primarily herbivorous animals. In southeastern Brazil, the δ13C values and isotopic niche breadth differences observed in juvenile green turtles suggest that variations in habitat (i.e., channel between the municipalities of Ilhabela and São Sebastião - “SSC” and region comprising the other two municipalities of Ubatuba and Caraguatatuba - “CAU”, as defined in this study based on oceanographic current dynamics) can influence their isotopic niche. The isotopic values observed in juvenile green turtles demonstrated a high degree of feeding behavior plasticity and individual variability, which were possibly influenced by the dynamic of oceanographic currents and seasonal nutrient inputs. These findings help to elucidate the feeding behavior of green turtles at different life stages and the potential influence of oceanographic current dynamics in key feeding sites for juvenile green turtles.

Zebrafish (Danio rerio) distinguish between two human caretakers and their associated roles within a captive environment

Zebrafish have become a popular biomedical model in recent decades, and are now maintained in laboratories worldwide. However, living within a captive environment can introduce novel environmental stressors and experiencing stress chronically can negatively affect animal welfare and, if applicable, how study results are interpreted. One method to potentially alleviate stress within captive environments is to introduce signaled predictability, i.e., conditioning captive populations to anticipate a future event by associating a visual or audio cue with the impending stimulus. A low-cost and easily accessible cue could be the caretakers themselves. Previous research has shown that archerfish can associate and distinguish between pictures of human faces, not human beings themselves. Therefore, it remains to be seen if fish, such as zebrafish can distinguish between two human caretakers, associated with different husbandry tasks. For this study, zebrafish were exposed to a caretaker who fed the fish only and a caretaker who chased the fish with a net, i.e., associated with an acute stressor. Caretaker duties were counterbalanced across two isolated laboratory shelving racks. Before performing tasks, the caretaker presented their face to all 10 fish tanks and then recorded the number of fish in the feeding area immediately. It was found that presentation of the stressor-caretaker did not significantly affect the number of fish within the feeding area, however, presentation of the caretaker associated with feeding led to a significant increase in the number of fish in the feeding area. By the end of the experiment, fish were more likely to be found in this area following the feeding-associated caretaker presentation, compared to the stressor-associated caretaker. These results suggest that zebrafish are capable of distinguishing between two human caretakers by learning to associate specific humans with husbandry procedures, particularly feeding. However, it is unclear exactly what visual cues, e.g., caretaker mannerisms, were utilized as caretaker faces were not isolated for presentation. Further research is needed to assess the repeatability of these results, as this research is novel, especially with respect to captive fish welfare.

Katepsin B İnhibitörü olan CA074'ün Serebral İskemi Modelinde Apoptoz ve Hücre Ölümü Üzerine Etkisi

Lysosomes and cathepsins, the most common hydrolytic enzymes in lysosomes, are available in the different models of cell death as necrosis and apoptosis. This study investigated the effect of cathepsin B-selective inhibitor CA-074 on apoptotic and necrotic neuronal cell death. Focal cerebral ischemia which has been formed by occlusion of the three-vessel consisting permanent middle cerebral artery occlusion and temporary bilateral common carotid artery occlusion for 60 minutes was selected as ischemia model. Two sets of rats were used in this study. The rats in the first set were used formeasurement of sulfhydryl groups in the lysosomal membrane, lysosomal integrity, cathepsins B and L activities and caspase-3 activity. The rats in the second set were used as histological study including "hematoxylin and eosin" for the detection of necrotic neuronal deathand "TUNEL" staining for the detection of apoptotic neuronal death. 4 mg/kg CA-074 was administered intravenouslyin the treatment group. CA-074 has substantially reduced levels of cathepsins B and L compared to ischemia and solvent groups (respectively, p<0.05 and p<0.01). Similarly, CA-074 has reduced increase in caspase-3 activity compared to ischemia and solvent groups (p<0.05). While the number of eosinophilic (necrotic) and apoptotic neurons has highly increased in post-ischemic cerebral tissue in middle cerebral artery feeding area (p<0.001), CA-074 could only reduce significantly the number of apoptotic neurons (p<0.05). CA-074 has reduced apoptotic neuronal death by inhibiting caspase and cathepsin activity. It may be useful that CA074 is used with other therapeutic drugs in stroke patients.

Multi-level assessment of the origin, feeding area and organohalogen contamination on salmon from the Baltic Sea

The Atlantic salmon (Salmo salar) population in the Baltic Sea consists of wild and hatchery-reared fish that have been released into the sea to support salmon stocks. During feeding migration, salmon migrate to different parts of the Baltic Sea and are exposed to various biotic and abiotic stressors, such as organohalogen compounds (OHCs). The effects of salmon origin (wild or hatchery-reared), feeding area (Baltic Main Basin, Bothnian Sea, and Gulf of Finland), and OHC concentration on the differences in hepatic proteome of salmon were investigated. Multi-level analysis of the OHC concentration, transcriptome, proteome, and oxidative stress biomarkers measured from the same salmon individuals were performed to find the key variables (origin, feeding area, OHC concentrations, and oxidative stress) that best account for the differences in the transcriptome and proteome between the salmon groups. When comparing wild and hatchery-reared salmon, differences were found in xenobiotic and amino acid metabolism-related pathways. When comparing salmon from different feeding areas, the amino acid and carbohydrate metabolic pathways were notably different. Several proteins found in these pathways are correlated with the concentrations of polychlorinated biphenyls (PCBs). The multi-level analysis also revealed amino acid metabolic pathways in connection with PCBs and oxidative stress variables related to glutathione metabolism. Other pathways found in the multi-level analysis included genetic information processes related to ribosomes, signaling and cellular processes related to the cytoskeleton, and the immune system, which were connected mainly to the concentrations of Polychlorinated biphenyls and Dichlorodiphenyltrichloroethane and their metabolites. These results suggest that the hepatic proteome of salmon in the Baltic Sea, together with the transcriptome, is more affected by the OHC concentrations and oxidative stress of the feeding area than the origin of the salmon.

Microsatellites and the Major Histocompatibility Complex of the Atlantic Walrus <i>Odobenus rosmarus rosmarus</i> (Linnaeus, 1758) in Haulouts of the Barents Sea

The allelic diversity of the DQB gene of the major histocompatibility complex (MHC) in Atlantic walrus from the European part of the Arctic was analyzed for the first time. We studied animals from the haulouts located on the Franz Josef Land archipelago and near the northern tip of Novaya Zemlya. We demonstrated that there are significant differences for this locus between the two studied haulouts. Simultaneous analysis of microsatellite loci reveals a lower level of differentiation, and also suggest that animals from more than one spatial-geographical stock (population) gather at the summer haulout on Novaya Zemlya. It has been suggested that individuals with different MHC genotypes may prefer different feeding areas, regardless of the areas of residence during the breeding season.

DYNAMICS AND MANAGEMENT OF PELAGIC SARGASSUM SPP. IN THE MEXICAN CARIBBEAN

Sargassum fluitans and S. natans (sargasso) are species of brown floating algae. They are found in the Atlantic, concentrated the Sargasso Sea, and also, since 2011, in the Great Altantic Sargassum Belt (Wang et al., 2019). Floating masses of sargasso offer resting, reproduction and feeding areas for many species (some of economic interest), and serve as a biological connectivity vector. However, since late 2014, massive quantities of sargasso have appeared on the coasts of the Mexican Caribbean. This has brought serious negative impacts, such as mortality of nearshore benthic flora and fauna, beach erosion, pollution, a decrease in tourism and high costs in managing the impacts (Chavez et al., 2020). Depending on hydrodynamic conditions, sargasso is transported to the coasts (beaching) or remains offshore, carried away by the ocean currents of the Atlantic. One of the main challenges in understanding sargasso dynamics has been the unpredictability of the influx, as sargasso concentrations in the ocean vary seasonally and interannually, and the ocean concentrations of sargasso and the beached biomass do not always coincide. Field observations, satellite imaginary analysis and numerical modelling have been used in various studies to understand the dynamics of sargasso.

Observed trends in scavenging by common bottlenose dolphins (Tursiops truncatus truncatus) in for‐hire fisheries in the eastern U.S. Gulf of Mexico

AbstractInteractions between bottlenose dolphin and recreational rod and reel fisheries are a complex issue for resource managers in the United States, which may impact anglers' catch and lead to dangerous situations for scavenging or depredating dolphins. To examine this issue, we analyzed data collected by observers on for‐hire fishing vessels off the eastern U.S. Gulf Coast from 2009 to 2020. A generalized additive model indicated number of anglers, number of discarded fish, proximity to shore, prior scavenging events, type of released fish, and area fished were all significant predictors of scavenging by dolphins. The Florida panhandle had the highest odds of scavenging, while scavenging in the Big Bend and Tampa Bay has increased through time. The Florida panhandle is a well‐known area for illegal feeding of dolphins, suggesting human behavior may be influencing fisheries interactions. Model outputs indicate that dolphins are primarily cuing on fishing activity rather than number of discards, but are more likely to scavenge discards from the family Lutjanidae (snappers), which comprised 40% of observed discards but 80% of scavenging events. This study highlights factors influencing the frequency of dolphin scavenging events, guiding managers and scientists on additional studies and mitigation measures needed to address this issue.

Mobilization of persistent organic pollutants in humpback whales: Insights from feeding areas in the Antarctic peninsula and Strait of Magellan to migration, breeding, and calving grounds along the Brazilian coast

Southern Hemisphere Megaptera novaeangliae undertake the longest migration, which reflect their exposure to lipophilic contaminants. To assess these changes, persistent organic pollutants were analyzed in blubber samples of humpback whales from three regions: the Antarctic Peninsula (n = 46), the Strait of Magellan, Chile (n = 22), and the Brazilian coast (n = 38). The similarity in PCB and HCB levels between individuals from feeding grounds and breeding grounds suggests contamination during feeding. The whales around the Antarctic Peninsula exhibited a predominance of tetrachlorobiphenyl PCBs. Whales feeding in the Strait of Magellan showed a slight prevalence of 5Cl biphenyls, likely due to their consumption of subantarctic krill species as well as small fishes potentially contaminated by industrial activities in Chile. The dominance of 5-6Cl congeners in whales in Brazil, may be attributed to the extreme physiological changes during fasting when whales utilize blubber reserves and metabolize lighter congeners, or transfer them to their calves.

Essential and toxic elements in juvenile migratory commercial fish species in the Paraná River alluvial valley (South America): an approach for aquatic environmental monitoring.

The Paraná River is the sixth largest in the world, and the lower section of the river is one of the largest and most productive floodplain wetlands in South America. The alluvial plain is an important habitat for nursery and feeding areas for commercial fish; however, it has been heavily anthropized due to industries, agricultural activities, and the growth and expansion of metropolitan areas. The aim of this study was to determine element accumulation (As, Cd, Cr, Cu, Fe, Mn, Pb, and Zn) in young-of-the-year fish muscle from a floodplain lagoon of the lower Paraná River (Argentina) during summer and winter seasons, in relation with abiotic matrices (water and sediment). Four commercial fish species were assessed: sábalo (Prochilodus lineatus), boga (Megaleporinus obtusidens), dorado (Salminus brasiliensis), and pirapitá (Brycon orbignyanus). The concentrations of eight elements were detected by quadrupole inductively coupled plasma mass spectrometry. In water samples, Cd, Cr, Mn, Fe, and Zn levels were under the permissible limits for aquatic biota protection in both seasons, except for Pb (> 1 μg L-1) and Cu (> 2 μg L-1). In sediment, the average concentrations of all elements were under the limits set by national and international regulatory authorities. Differences in elemental concentrations between species and seasons were found. In general, the levels of elements in water were higher in summer than in winter, while in sediment, the lowest concentrations of elements were detected during the summer. The order of element concentration in fish muscle was Cd (0.01-0.04 μg g-1) < As (0.02-0.16 μg g-1) < Pb (0.03-0.23 μg g-1) < Mn (0.77-4.32 μg g-1) < Cu (1.01-4.07 μg g-1) < Cr (1.09-4.30 μg g-1) < Zn (15.8-31.7 μg g -1) < Fe (12.6-49.7 μg g-1). The accumulation assessment showed that the four fish species significantly accumulate Cr, Cu and Zn, and As and Zn from water and sediment, respectively. The correlation analysis showed a relationship between fish size and As, Cr, Cu, Fe, Mn, and Zn concentrations. Similarly, the highest values of element concentrations in muscle were detected during the summer when the fishes are early juveniles. The level of As, Cd, and Pb detected in B. orbignyanus, M. obtusidens, and P. lineatus juveniles suggested that these species had the potential to be used as biomarkers for assessing accumulation of toxic elements in the environment. Also, this study reveals that the accumulation patterns differ between size and fish species, which should be a considered insight at the moment of selecting a bioindicator to monitor pollution in the ecosystem.

Construction of Recombinant Escherichia coli with a High L-Phenylalanine Production Yield from Glucose

L-phenylalanine is an important aromatic amino acid that is widely used in the area of feed, food additives, and pharmaceuticals. Among the different strategies of L-phenylalanine synthesis, direct microbial fermentation from raw substrates has attracted more and more attention due to its environment friendly process and low-cost raw materials. In this study, a rational designed recombinant Escherichia coli was constructed for L-phenylalanine production. Based on wild type E. coli MG1655, multilevel engineering strategies were carried out, such as directing more carbon flux into the L-phenylalanine synthetic pathway, increasing intracellular level of precursors, blocking by-product synthesis pathways and facilitating the secretion of L-phenylalanine. During 5 L fed batch fermentation, recombinant E. coli MPH-3 could produce 19.24 g/L of L-phenylalanine with a yield of 0.279 g/g glucose. To the best of our knowledge, this is one of the highest yields of L-phenylalanine producing E. coli using glucose as the sole carbon source in fed-batch fermentation.

Cod distribution in the Barents Sea under climate changes

The aim of the paper is to assess the impact of climate changes and oceanographic conditions on the distribution of cod stocks in the Barents Sea in recent decades. The material for the study was oceanographic data obtained during surveys in the Barents Sea by PINRO and other available information on hydrometeorological conditions of the sea in 1981–2021, as well as data onRussian catches of cod in the Barents Sea based on bottom trawl fishing operations. Methods of descriptive statistics as well as comparative, correlation and regression analyses were applied. Results: The modern changes in the climate and oceanographic conditions of the Barents Sea are described. Since the early 1980s, the warming has been observed against the background of increasing storm activity, having peaked in 2016. After that, despite still warm and low-ice conditions, there has been a cooling trend in the Barents Sea. Under climate changes in recent decades, cod made increasingly long migrations north and east, spreading more widely in the feeding areas. The most informative predictors in assessing the impactof climate changes and oceanographic conditions on the distribution of cod stocks in the Barents Sea were Arctic ice extent, area-averaged temperature at a depth of 100 m, Atlantic water area in the 50–100 m layer, and parameters of the Barents Sea thermal frontal zones. Practical significance: The obtained results are useful for a better understanding of the processes occurring in the Barents Sea ecosystem and, in the future, will be used to predict cod distributions in the sea, depending on oceanographic conditions and climate changes.

Microbiological Quality Assessment of Drinking Water at Al-Hayy City, Southern Iraq.

The microbial quality of drinking water which distributed form Al-Hayy water treatment plant and number of residential areas fed by these water treatment plant was studied each month over six month during a period extended from the October 2016 to April 2017,through the purification stages up to residential sites at different areas situated with various distances from the supplying source, two samples were taken monthly. This station derived their water from AL-Gharraf River in the southeastern part of Iraq, where the feed areas of the city with drinking water. This study included detection of bacteria, evidence of contamination of water (coliform, faecal coliform, Escherichia coli, faecal streptococcus bacteria and total bacteria count), also some physical and chemical variables ware like (temperature, turbidity, free residual chlorine and pH) . Results of Bacteriological tests showed increasing in TPC, TC, FC, E.coli and FS bacteria in December and January in all study locations as compared to those of the other months for water plant raw and drinking water and the FS values were less than other bacterial types for water plant. The TPC results of drinking water exceed 100 cell/ml, the allowable limit for drinking water, for all samples of water plant. On the other hand the TC, FC and E.coli exceeded zero cell/100ml, the allowable limit for drinking water, in many drinking water samples for water plant with increasing of temperature in summer months. Physiochemical tests showed that air temperature at sampling time was varied between17 and 34°C and between11.5 and 29°C, for water temperature at sampling time also. The results of pH means were within the allowable limit, ranging from 7.2 in October to 7.9 in April.The highest mean value of turbidity recorded for raw water was in December with 89 NTU and the lowest value was in April with 30 NTU, while the highest mean value recorded for Drinking water was 20 NTU again in December and the lowest value was 1 NTU in April. The highest mean value of residual chlorine was recorded in March with 3.8 mg/L, the lowest value was 0 mg/L in some of the farthest points of the plant.

An automated, low-latency environment for studying the neural basis of behavior in freely moving rats

BackgroundBehavior consists of the interaction between an organism and its environment, and is controlled by the brain. Brain activity varies at sub-second time scales, but behavioral measures are usually coarse (often consisting of only binary trial outcomes).ResultsTo overcome this mismatch, we developed the Rat Interactive Foraging Facility (RIFF): a programmable interactive arena for freely moving rats with multiple feeding areas, multiple sound sources, high-resolution behavioral tracking, and simultaneous electrophysiological recordings. The paper provides detailed information about the construction of the RIFF and the software used to control it. To illustrate the flexibility of the RIFF, we describe two complex tasks implemented in the RIFF, a foraging task and a sound localization task. Rats quickly learned to obtain rewards in both tasks. Neurons in the auditory cortex as well as neurons in the auditory field in the posterior insula had sound-driven activity during behavior. Remarkably, neurons in both structures also showed sensitivity to non-auditory parameters such as location in the arena and head-to-body angle.ConclusionsThe RIFF provides insights into the cognitive capabilities and learning mechanisms of rats and opens the way to a better understanding of how brains control behavior. The ability to do so depends crucially on the combination of wireless electrophysiology and detailed behavioral documentation available in the RIFF.

Ecological traits do not predict the uptake of microplastics by fishes in a Neotropical River.

Pollution by synthetic polymers is even more problematic to the environment when this material is fragmented into small portions, forming microplastics (MPs). We analyzed the contamination of ichthyofauna by MPs in an important river of the Atlantic Rainforest in regard to abundance, diversity of morphotypes, polymers, colors, and sizes of the synthetic particles in 20 species of fish. Fish were collected in November 2019 and in March 2020 in five sites along the Pomba River. Of the 101 fish analyzed, 49 (49%) presented MPs in at least one organ. Of the 20 species of fish collected 13 included individuals with at least one MP in their analyzed organs. The organs, trophic categories and feeding areas did not affect the general abundance of MPs types. Blue MPs were predominant, followed by the colors black, red, and white. MP fibers represented 91% of total MPs. Most MPs were between 2 and 3 mm in size. Polyethylene terephthalate (PET), polypropylene (PP), polyamide (PA), polyvinylidene chloride "Nylon" (PVDC), and high-density polyethylene (HDPE) were detected in the fishes. The exposure of the fish species to MPs was associated mainly with individual size and species-specific aspects, regardless of ecological traits. Considering that 55% of the fish species studied are consumed by humans, it is necessary to study the potential impact of MP ingestion on human health and to understand to what extent we may be consuming both plastic particles and contaminants that are adsorbed to MPs.

Influence of landfill use on nest‐site selection and breeding success in white storks

AbstractLandscape transformation by humans through habitat degradation, agriculture intensification and urbanization results in the loss of natural feeding areas. However, populations of certain species have adapted to these changes and benefit from some anthropogenic food sources as well as an absence of predators and milder environmental conditions in urban landscapes. Although breeding near landfills secures food availability and saves energy and time spent on foraging activities, the poor food quality and risks associated with these facilities imply some fitness costs. Our study shows the effects of landfills on nest‐site selection and breeding success in white storks (Ciconia ciconia). Birds breeding near landfills occupy more urban areas where many structures are available to nest, while breeding pairs 20–30 km from landfills select nest sites with high‐quality food sources in the vicinity such as pastures, meadows and agro‐forestry areas. Furthermore, we demonstrate that habitat quality in the surrounding area is more relevant than landfills for breeding outcomes, but both of these are crucial for brood size. The number of fledglings was higher at a medium distance to the landfill than at 20–30 km from the landfill, but not near the landfill (0–10 km). This suggests that the best strategy includes food from landfills as a complementary or alternative food source. Future studies should further investigate if these shifts in habitat preference are permanent, and the potential impact of habitat degradation and landfill closures at a population level, for this species.

Diet of hawksbill turtles (Eretmochelys imbricata) in the Gulf of California, Mexico

Abstract Hawksbill turtles (n = 56) in a foraging ground around Isla San Jose, Gulf of California, Mexico, were caught, measured, and their skin and scutes sampled. Tissue samples from putative prey species were collected from observed hawksbill feeding areas in the foraging ground. Measurements of each turtle's straight carapace length were used to estimate the average life stage of the population. Tissue samples were processed for stable carbon and nitrogen isotope analysis to estimate foraging habits of turtles in this location. The majority (96.4%) of measured individuals' straight carapace length fell in the size range considered to be juveniles. A Bayesian mixing model analysis of the δ13C and δ15N values of hawksbill skin and potential prey indicated that hawksbills consume primarily invertebrates and algae, with lesser contributions from seagrass and mangrove material. There was a positive linear relationship between turtle size and the δ13C values from scute samples, and an increase in the δ13C values of five individuals recaptured in subsequent years suggested a potential location shift from a pelagic habitat in the turtles' post‐hatching, earliest juvenile years to the nearshore foraging area around Isla San Jose in their later juvenile years.

Potential Impact of Climate Change on Salmonid Smolt Ecology

The migratory life history of anadromous salmonids requires successful migration between nursery, feeding, and spawning habitats. Smolting is the major transformation anadromous salmonids undergo before migration to feeding areas. It prepares juvenile fish for downstream migration and their entry to seawater. We reviewed the effects of climate change on smolt ecology from the growth of juveniles in fresh water to early post-smolts in the sea to identify the potential effects of climate change on migratory salmonid populations during this period in their life history. The focus was especially on Atlantic salmon. The shift in suitable thermal conditions caused by climate change results in Atlantic salmon expanding their range northward, while at the southern edge of their distribution, populations struggle with high temperatures and occasional droughts. Climatic conditions, particularly warmer temperatures, affect growth during the freshwater river phase. Better growth in northern latitudes leads to earlier smolting. Thermal refuges, the areas of cooler water in the river, are important for salmonids impacted by climate change. Restoring and maintaining connectivity and a suitably diverse mosaic habitat in rivers are important for survival and growth throughout the range. The start of the smolt migration has shifted earlier as a response to rising water temperatures, which has led to concerns about a mismatch with optimal conditions for post-smolts in the sea, decreasing their survival. A wide smolt window allowing all migrating phenotypes from early to late migrants’ safe access to the sea is important in changing environmental conditions. This is also true for regulated rivers, where flow regulation practices cause selection pressures on migrating salmonid phenotypes. The freshwater life history also affects marine survival, and better collaboration across life stages and habitats is necessary among researchers and managers to boost smolt production in rivers. Proactive measures are recommended against population declines, including sustainable land use in the catchment, maintaining a diverse mosaic of habitats for salmonids, restoring flow and connectivity, and conserving key habitats.