Colonization and dispersal patterns of the invasive American brine shrimp Artemia franciscana (Branchiopoda: Anostraca) in the Mediterranean region

Cysts of the brine shrimp Artemia franciscana are harvested from the Great Salt Lake (GSL) and San Francisco Bay (SFB) saltworks in the USA, and marketed worldwide to provide live food for aquaculture. This species has become invasive across several countries. We investigated (1) if the introduced populations in the Mediterranean region could have originated from these USA populations, (2) how the genetic diversity of Mediterranean compares to that at GSL and SFB, and (3) if genetic patterns in the Mediterranean can shed light on colonization routes. We sequenced a fragment of the cytochrome c oxidase subunit I and screened microsatellites loci from Mediterranean populations and the two putative USA sources. Haplotypes from Mediterranean populations were identical or closely related to those from SFB and GSL, and not related to other available American populations. Microsatellite analyses showed a reduced population diversity for most Mediterranean populations suggesting bottleneck effects, but few populations were showing similar or higher genetic diversity than native ones, which are likely to be admixed from both GSL and SFB because of multiple introductions. Results suggest natural dispersal, potentially via flamingos, between two Spanish populations. Our analyses show that all invaded populations could have originated from those commercialized USA populations. © 2013 Springer Science+Business Media Dordrecht

The shine of precious metals around the global financial crisis

Figuerola-Ferretti thanks the Spanish Ministry of Education and Science for support under grants MICINN ECO2010-19357, ECO2012-36559 and ECO2013-46395, and McCrorie, The Carnegie Trust for the Universities of Scotland under grant no. 31935.We analyze the price behavior of the main precious metals – gold, silver, platinum and palladium – before, during and in the aftermath of the 2007–08 financial crisis. Using the mildly explosive/multiple bubble technology developed by Phillips, Shi and Yu (2015, International Economic Review 56(4), 1043–1133), we find significant, short periods of mildly explosive behavior in the spot and futures prices of all four metals. Fewer periods are detected using exchange-rate adjusted prices, and almost none when deflated prices are used. We assess whether these findings are indicative of bubble behavior. Convenience yield is shown to have little efficacy in this regard, while other fundamental proxy variables and position data offer only very limited evidence against prices having been anything other than fundamentals-driven. Possible exceptions are in gold in the run-up to the highpoint of the financial crisis, and in silver and palladium around the launch of specific financial products. Some froth, however, is reported and discussed for each metal.PostprintPeer reviewe

Immigration enhances fast growth of a newly established source population

Immigration and local recruitment play a central role in determining the growth rate of breeding populations. Unraveling these processes in newly established pop-ulations is of great importance to increase our understanding of how species change their distributions in response to global change. We studied the largest colony of glossy ibis (Plegadis falcinellus) in Western Europe (established in 1996 in Doñana, SW- Spain) by using capture- recapture methods, count estimates, and projection matrix modeling to: (1) test the effect of resource availability and competition on local recruitment dynamics, (2) inves-tigate the contribution of local recruitment vs. immigration on population growth, and (3) assess the role of this population in source/sink dynamics. We found different dynamics before and after the establishment of satellite colonies in Doñana in 2004. Between 1996 and 2003, the population increased rapidly, fueled by immigrants (≈58 breeding females/yr). Between 2003 and 2007, however, both colony size increase and immigration were negligible. Immigration played a major role in colony growth, but simultaneously this colony was a source population driving expansion of the species range as suggested by (1) absolute and relative estimates of the observed growth rate relative to that predicted by self- recruitment, and (2) numerous observations of Doñana- born individuals breeding elsewhere. Local recruitment, which was particularly high for first- year individuals (prob-ability >0.8 for the early study years), was not directly related to resource availability or previous- year breeding success. Local recruitment decreased rapidly at a threshold popu-lation size, however, when other satellite colonies became established at Doñana. Our study suggests that even when recruitment at an early age and high productivity are observed, immigration can still play a pivotal role in promoting the fast growth of new populations at the edge of a species range, at least until density- dependent effects arise. This process can be so fast that within a few years a new population can itself become a source population, further driving range expansion of the species.Peer reviewe

Intracolonial differences in the infestation by Haemoproteus lari on Yellow-legged Gulls Larus cachinnans

The prevalence and intensity of Haemoproteus lari infestation were studied in a colony of Yellow-legged Gulls (Larus cachinnans) on the Medes Islands (NE Spain) during 1994 and 1995. Prevalence did not differ between years, sexes, clutch sizes or nesting habitats . More heavily infected females tended to lay smaller clutches and to be in a leaner body condition; in males, intensity of parasites was unrelated to their clutch size and their body condition. These results are partially consistent with the detrimental effect of blood parasites, but also with a tendency for stressed birds to relapse . Intensity of parasitemia differed both between years and among nesting habitats of the gullery, probably as a result of differences in bird quality at the time of sampling. We suggest that these effects should be controlled for in studies dealing with parasites in colonial nesting birds

Adaptive drift and barrier-avoidance by a fly-forage migrant along a climate-driven flyway

BACKGROUND: Route choice and travel performance of fly-forage migrants are partly driven by large-scale habitat availability, but it remains unclear to what extent wind support through large-scale wind regimes moulds their migratory behaviour. We aimed to determine to what extent a trans-equatorial fly-forage migrant engages in adaptive drift through distinct wind regimes and biomes across Africa. The Inter-tropical Front (ITF) marks a strong and seasonally shifting climatic boundary at the thermal equator, and we assessed whether migratory detours were associated with this climatic feature. Furthermore, we sought to disentangle the influence of wind and biome on daily, regional and seasonal travel performance. METHODS: We GPS-tracked 19 adult Eleonora’s falcons Falco eleonorae from the westernmost population on the Canary Islands across 39 autumn and 36 spring migrations to and from Madagascar. Tracks were annotated with wind data to assess the falcons’ orientation behaviour and the wind support they achieved in each season and distinct biomes. We further tested whether falcon routes across the Sahel were correlated with the ITF position, and how realized wind support and biome affect daily travel times, distances and speeds. RESULTS: Changes in orientation behaviour across Africa’s biomes were associated with changes in prevailing wind fields. Falcons realized higher wind support along their detours than was available along the shortest possible route by drifting through adverse autumn wind fields, but compromised wind support while detouring through supportive spring wind fields. Movements across the Sahel-Sudan zone were strongly associated to the ITF position in autumn, but were more individually variable in spring. Realized wind support was an important driver of daily travel speeds and distances, in conjunction with regional wind-independent variation in daily travel time budgets. CONCLUSIONS: Although daily travel time budgets of falcons vary independently from wind, their daily travel performance is strongly affected by orientation-dependent wind support. Falcons thereby tend to drift to minimize or avoid headwinds through opposing wind fields and over ecological barriers, while compensating through weak or supportive wind fields and over hospitable biomes. The ITF may offer a climatic leading line to fly-forage migrants in terms of both flight and foraging conditions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40462-021-00272-8