A Novel Locality for the Observation of Thousands of Passerine Birds during Spring Migration in Los Angeles County, California

Avian migration is a spectacular phenomenon, representing the annual movements of billions of birds globally. Because the greatest diversity and numbers of birds migrate at night, opportunities to observe active migration are rare. At a number of localities in North America, however, observers can quantify movements of many typically nocturnal migrants during daylight where they continue after dawn. Such locations have provided much information about species-specific phenology, status, and orientation during migration. Localities where morning flights of land birds can be observed are unevenly distributed, however, and are little reported along the Pacific coast. Here we describe a novel location for the observation of spectacular morning flights of nocturnal migrants during spring migration at Bear Divide, in the western San Gabriel Mountains, Los Angeles County, California. In two years of informal surveys at the site, we have recorded at least one morning with an estimated ~13,500 individual birds passing. Our preliminary analyses suggest that the peak of a species’ migration at Bear Divide is correlated with the latitude of a species’ breeding, being later in the spring as that latitude increases. Our data from Bear Divide provide an independent perspective on migration as quantified by local radar. Further work at this locality may help inform our knowledge of migration phenology and population trends.

A new Oligocene-Miocene tree from Panama and historical Anacardium migration patterns

Migration of Boreotropical megathermal taxa during the Oligocene and Miocene played a key role in assembling diversity in tropical regions. Despite scattered fossil reports, the cashew genus Anacardium offers an excellent example of such migration. The fossil woods described here come from localities in Veraguas, Panama mapped as Oligocene-Miocene. We studied, described, and identified two well-preserved specimens using wood anatomical characteristics and completed extensive comparisons between fossil and extant material. The studied fossil woods share several diagnostic features with the modern Anacardium genus, including large solitary vessels, large intervessel-pitting, a simple vessel-ray pitting pattern, and mostly 1–3 seriate rays with large rhomboidal solitary crystals. We propose a new fossil species named Anacardium gassonii sp. nov., that adds an essential piece to the understanding of the historical biogeography of the genus. In addition, our findings confirm previous interpretations of this species’ migration from Europe to North America and its crossing through Panama, leading to subsequent diversification in South America. This discovery provides an important link to the historical migration patterns of the genus, supporting the notion of an Eocene migration to the Neotropics via Boreotropical bridges, as well as an Oligocene-Miocene crossing of Central America followed by diversification in South America.

The Role of International Cooperation in Invasive Species Research

The root cause of the biological invasion problem is globalization, which has facilitated the planet-wide breakdown of biogeographic barriers to species migration (Mooney and Hobbs 2000). In order to understand and manage the problem, coordination on a global scale is essential, and international cooperation among affected countries as well as with countries of pest origin must therefore play a critical role in virtually all aspects of research on biological invasions (Chornesky et al. 2005; McNeely et al. 2001; Perrings et al. 2010; Wingfield et al. 2015). Here we discuss key aspects of research on biological invasions, where international collaboration and coordination are important, and what infrastructures play a role in this work.

Possible implications of sea level changes for species migration through the Suez Canal

The Mediterranean and Red Sea, which were connected via the Suez Canal during the 19th century after eons of separation, host two distinctive ecosystems. Species invasion through the Suez Canal from the Red Sea vastly influences the ecology of the Mediterranean, but the level of reverse migration is assumed to be negligible. We present the first reconstructed flow transport record through the canal during the period 1923–2016. According to this reconstruction, the flow intensity and direction through the canal are strongly influenced by seasonal and long-term sea-level changes, which could also play a role in the characteristics of species migration through it. Our record not only supports previous observations of the unidirectional invasion until the 1980s and the accelerated species migration rates to the Mediterranean ever since, but also suggest that southward migration could have become possible since the early 1980s. The southward flow was primarily enhanced by Indian Ocean cooling and the Eastern Mediterranean Transition in deep water formation during the period 1980–2000. It was then gradually reduced by accelerated sea-level rise in the northern Indian Ocean.

Species Migration & Conservation of Hilsa (Tenulosa Ilisha), Ray-Fish Using the Digital Techniques

Research communication dealt here, a digital application on a species migration & conservation of Hilsa (Tenulosa ilisha), Ray-fish of Ganges and others using the digital technique and described. Application comes in Hilsa, Ray fish and few others are described based on one of the most important water quality parameters, fisheries for migration and conservation. Known that Hilsa has got an immense importance among the fish lovers and to the fish-eating people because of taste and nutrition. Hilsa is one of the most popular among the fishes found in Bay, Estuary or Rivers of Indian Continent. A single matured Hilsa can be weighing around 6 kg. When get matured. Distribution of Hilsa fish are found in Bays, in and around the great Sundarbans and migrates to adjacent waters across the upward of river stretches mainly Ganges, Padma and Godavari rivers while to breed. As like most other fish species this Hilsa species migrates in search of a suitable Total Dissolved Solids (TDS), and in this communication, the study area from coastal Bay of Bengal to the upward fresh-waters of river Ganges. The extent of migration may depend on the fact that till this species gets suitable minimum total dissolved solids on the way to migration while to perform the course of natural breeding. During the breeding period, like every other fish species, this Hilsa fish tries to find a minimum TDS to breed naturally. The threshold value of TDS can easily be detectable computer and electronics devices or simply a TDS meter. This research-study found that a Hilsa fish can breed naturally when the TDS value may become closer to 95-105 ppm, found near up-to the middle stretch of river Ganges regions. Species Hilsa, can migrate mere a 100-300 km or even more in search of mentioned suitable TDS and after the course of natural breeding, the species re-migrate to Bay along with all juveniles unless being caught. For growth and maturity of Hilsa fish like to prefer TDS of a range, 120 to 260 ppm, usually at the Sundarban Estuary and coastal regions of Bay of Bengal.

Mining citizen science data to explore stopover sites and spatiotemporal variation in migration patterns of the red-footed falcon

Citizen science data have already been used to effectively address questions regarding migration, a fundamental stage in the life history of birds. In this study, we use data from eBird and from 3 additional regional citizen science databases to describe the migration routes and timing of the red-footed falcon Falco vespertinus in the Mediterranean region across 8 years (2010–2017). We further examine the seasonal and yearly variation in migration patterns and explore sites used during the species migration. Our results suggest that the autumn passage is spatially less variable and temporally more consistent among years than in spring and that birds migrate faster in spring than in autumn. The species seems to be more prevalent along the Central Mediterranean during spring migration, probably as a result of the clockwise loop migration that red-footed falcons perform. There was a high variation in annual median migration dates for both seasons as well as in migration routes across years and seasons. Higher variation was exhibited in the longitudinal component thus indicating flexibility in migration routes. In addition, our results showed the species’ preference for lowlands covered with cropland and mosaics of cropland and natural vegetation as stopover sites during migration. Stopover areas predicted from our distribution modeling highlight the importance of the Mediterranean islands as stopover sites for sea-crossing raptors, such as the red-footed falcon. This study is the first to provide a broad-scale spatiotemporal perspective on the species migration across seasons, years and flyways and demonstrates how citizen science data can inform future monitoring and conservation strategies.