Large scale climate affects the timing of spring arrival but local weather determines the start of breeding in a northern Little Tern (Sternula albifrons) population

Abstract In migratory birds, the timing of arrival to the breeding grounds can be affected by weather on the migration routes and breeding sites at arrival. Timing of breeding can be affected by arrival dates but also by local weather conditions during the pre-breeding period. Because long-distance migrants arrive and breed late in the season, weather is thought to be less important, but more information is needed especially from seabirds that are vulnerable to climatic effects. I used observation data from the Little Tern (Sternula albifrons), a long-distance migrant, made by bird watchers during 2006–2016 to examine whether their spring arrival to the breeding grounds in Finland is associated with the large-scale weather pattern (the North Atlantic Oscillation; NAO index) or local weather. In addition, I used breeding data to examine whether the start of egg laying is associated with the annual first arrival dates, local weather or the NAO index. Spring arrival was associated with large scale weather patterns rather than local weather conditions. Little Terns arrived earlier when the April–May NAO index was positive being consistent with most migratory birds. However, early arrival dates did not translate to early timing of breeding which was more determined by local temperatures before egg laying. Arriving early allows preparation for breeding, e.g., courtship feeding, and makes it possible to start breeding when conditions become suitable for egg laying, and suggests that these long-distance migrants should be able to track advancing springs and start their breeding in the most optimal time.Tiivistelmä Säätekijöiden vaikutus pikkutiirojen (Sternula albifrons) ensisaapumiseen ja pesinnänaloitukseen Muuttolintujen saapuminen pesimäpaikoilleen on usein yhteydessä muuttoreittien ja pesimäpaikkojen säätilaan. Pesinnänaloittaminen voi puolestaan olla yhteydessä saapumisajankohtaan tai pesimäpaikoilla vallitseviin kevään olosuhteisiin ennen muninnan aloittamista. Koska pitkänmatkan muuttajat saapuvat ja pesivät myöhään, sääolojen ajatellaan vaikuttavan niihin verrattain vähän. Lisätietoa sään merkityksestä muuton ja pesinnän aloittamiseen tarvitaan etenkin merilinnuista, jotka ovat erityisen alttiita ilmaston vaikutuksille. Käytin lintuharrastajien vuosina 2006–2016 keräämää havaintoaineistoa selvittääkseni milloin pikkutiira, joka on pitkänmatkanmuuttaja, saapuu pesimäpaikoilleen, ja ovatko kevään ensimmäiset havainnot yhteydessä muuttoaikana vallitsevaan laaja-alaiseen ilmastoon (Pohjois-Atlantin Oskillaatio indeksi, NAO-indeksi) tai paikalliseen säähän pesimäpaikoilla. Lisäksi käytin keräämääni pesimäaineistoa samalta ajanjaksolta tutkiessani, oliko kevään ensimmäisen pesän muninnan aloitus yhteydessä saapumisajankohtaan, NAO-indeksiin tai paikalliseen säähän. Ensisaapuminen oli yhteydessä huhti–toukokuun NAO-indeksiin, mutta ei niinkään paikallisiin sääoloihin. Pikkutiirat saapuivat aikaisin, kun NAO-indeksi oli positiivinen. Tuolloin vallitsee suotuiset sääolot jotka edistävät lintujen kevätmuuttoa. Saapumispäivä ei kuitenkaan vaikuttanut pesinnänaloitukseen, joka oli paremmin yhteydessä kevään lämpötilaan juuri ennen munintakauden alkamista. Aikainen saapuminen mahdollistaa pesintään valmistautumisen ja pariutumiseen liittyvät vaiheet, ja mahdollistaa tätä kautta olosuhteiden seuraamisen sekä pesinnänaloittamisen heti kun olosuhteet kehittyvät suotuisiksi. Saattaa siis olla, että pikkutiirat pystyvät vastaamaan ilmastonmuutoksen aiheuttamaan kevään aikaistumiseen, ja pystyvät pesimään optimaaliseen aikaan

Linking demography with dispersal and habitat selection for species conservation

Abstract In conservation biology, informed and sound management decisions depend on target specific information about the life history and demography of the endangered populations. I used long-term, individual-based life history data (breeding and capture-recapture data) to examine life-history and demography in order to assess population viability and management. My study systems consist of metapopulations of two endangered, long-distance migratory wader species breeding on Baltic coastal meadows, the Temminck’s stint (Calidris temminckii) and the Southern Dunlin (Calidris alpina schinzii), whose breeding habitats are mainly managed by livestock grazing. Demographic models indicated that both study populations were sinks, which persist through immigration due to low local recruitment insufficient to compensate for adult mortality or emigration. Philopatric Temminck’s stints had higher nest and apparent adult survival compared to immigrants. Consideration of dispersal status in population models resulted in the most realistic estimates of population growth and revealed a low demographic impact of immigrants. Immigrants had low return rates after reproductive failure, suggesting that the difference in apparent survival was partly caused by different breeding dispersal strategies. Thus, management actions improving reproduction, and thus site fidelity, should also influence viability. An artificial nest experiment indicated high trampling rates under recommended stocking rates on managed meadows. This was attributed to similar space use of nesting Dunlin and cattle. Cattle presence did not affect nest predation. Young Dunlin preferred intensively grazed low sward habitat over high sward habitat. Reproductive success was also higher in low sward habitat. However, nests in the preferred habitat had the highest risk of being trampled if not artificially protected. Thus, low sward habitat was found to work as an ecological trap if grazing was started too early in the breeding season. Due to the sink nature of the Dunlin population even small reductions in reproductive success caused by trampling were detrimental to long term viability. The results encourage continuation of the use of cattle grazing as a management tool, but also highlight the need for more detailed consideration of local grazing practices, especially when sketching management plans for endangered species.Tiivistelmä Uhanalaisten lajien suojelussa tehokkaiden suojelutoimien suunnittelu edellyttää tietoa hoitokohteen elinkierron eri vaiheista ja niiden demografisesta merkityksestä. Käytän tutkimuksessani pitkäaikaisaineistoja (pesintä ja merkintä-takaisinpyynti) kuvatakseni tutkimuslajien demografiaa ja arvioidessani populaatioiden elinkykyä sekä hoitotoimia. Tutkimuskohteinani ovat lapinsirrin ja etelänsuosirrin, kahden uhanalaisen kahlaajan, Perämeren rantaniityillä pesivät metapopulaatiot. Näiden lajien elinympäristöjä hoidetaan pääosin laiduntamalla. Demografinen mallinnus osoitti molempien populaatioiden olevan nielupopulaatioita, joiden säilyminen on tulomuuton varassa sillä poikastuotto ei kompensoi aikuisten kuolleisuutta ja poismuuttoa. Tutkimusalueella syntyneiden ja sinne rekrytoituneiden lapinsirrien pesä- ja aikuissäilyvyydet olivat paremmat kuin tulomuuttajilla. Tämän huomioiminen populaatiomalleissa tuotti realistisimman kasvukertoimen arvion ja osoitti paikallisten rekryyttien olevan tulomuuttajia merkittävämpiä populaation kasvun kannalta. Pesinnässään onnistuneet tulomuuttajat palasivat seuraavina pesimäkausina epäonnistuneita todennäköisemmin. Paikallisilla rekryyteillä vastaavaa eroa ei havaittu. Ilmiö heijastellee tulomuuttajien muuttoalttiutta myöhemminkin ja voi kertoa erilaisista pesimädispersaalistrategioista. Lisääntymismenestyksen parantaminen voisi parantaa elinkykyä myös pienentämällä poismuuttoa. Tekopesäkokeen perusteella pesien tallausriski oli laidunnetuissa ympäristöissä korkea vaikka laidunnuspaine noudatteli hoitosuosituksia. Tämä johtunee ainakin osin laskennallista korkeammasta todellisesta laidunpaineesta, mikä puolestaan johtui lintujen ja karjan yhtäläisestä tilankäytöstä. Rekrytoituvat suosirrit suosivat voimakkaasti laidunnettuja matalakasvuisia niittyjä, joissa poikastuotto oli parempi kuin, laiduntamattomilla niityillä. Toisaalta, tallausriski on voimakkaasti laidunnetuilla niityillä suuri ja jo pienetkin pesätappiot uhkaavat suosirripopulaation elinkykyä. Täten laitumet voivat toimia ns. ekologisina loukkuina, jos laidunnus aloitetaan liian aikaisin suhteessa pesintään. Laidunnus on kuitenkin suositeltava hoitomuoto, sillä se näyttää tuottavan parhaita pesimäympäristöjä etelänsuosirrille. Tulosten mukaan laidunnuksen ajoitusta, laajuutta ja laidunnuspainetta on muokattava kohdekohtaisesti, jotta saavutetaan paras tulos uhanalaisten lajien suojelun kannalta

Characteristics and Prognosis of Exercise-Related Sudden Cardiac Arrest

Introduction: The previous studies about exercise-related sudden cardiac arrest (SCA) have mainly focused on sports activity, but information related to SCA in other forms of physical exercise is lacking. Our aim was to identify characteristics and prognosis of SCA victims in the general population who suffered SCA during physical activity.Methods and results: We collected retrospectively all cases of attempted resuscitation in Oulu University Hospital Area between 2007 and 2012. A total of 300 cases were of cardiac origin. We only included witnessed cases with Emergency Medical System arrival time ≤15 min. Cases of low-intensity physical activity were excluded. A total of 47 SCAs occurred during moderate-to-vigorous physical activity (exercise-group) and 43 cases took place at rest (rest–group). The subjects in exercise-group were younger compared to the rest-group (60 ± 14 years vs. 67 ± 14 years, p = 0.016). The initial rhythm recorded was more often ventricular fibrillation (VF) in exercise-group compared to the rest-group (77 vs. 50%, p = 0.010). Pulseless electrical activity (PEA) was rare in exercise-group compared to the rest -group (2.1 vs. 14%, p = 0.033, respectively). Bystander cardiopulmonary resuscitation (CPR) was more often performed when SCA took place during physical exercise (47 vs. 23 %, p = 0.020). Survival rates to hospital discharge were higher in the exercise-group compared to the rest -group (49 vs. 9.3%, p < 0.0001).Conclusions: SCA occurring during physical activity is more frequently a result of VF and bystander CPR is more often performed. There is also a notably better survival rate to hospital discharge

Northward expanding resident species benefit from warming winters through increased foraging rates and predator vigilance

Abstract Species distributions shift northwards due to climate change, but the ecological mechanisms allowing range expansions are not fully understood. Most studies have concentrated on breeding seasons, but winter warming may also be important. Wintering distributions are restricted by food availability and temperature, which may also interact. Foraging in cold conditions requires adaptations as individuals have to be efficient in foraging, while staying warm and vigilant for predators. When the ambient temperature declines, foraging rates should be reduced due to increased time spent on warming behaviours. In addition, predator vigilance should decline, because more time has to be invested in foraging. Cold weather should limit northward expanding southern species in particular, while northern species should perform better in cold conditions. We tested this by studying temperature responses (between 0 and − 35 °C) among wintering birds at feeders. We compared foraging behaviours of two northward expanding southern species, the great tit (Parus major) and the blue tit (Cyanistes caeruleus) to a northern species, the willow tit (Poecile montanus). Foraging rate and vigilance decreased, and warming behaviour increased when temperatures declined. Importantly, the performance in these traits was poorer in the southern species compared to the willow tit. Furthermore, the response to decreasing temperatures in foraging rates and warming behaviour was stronger in the great tits than willow tits. As the winters become warmer, these mechanisms should increase wintering success of southern species wintering at high latitudes, and lead to higher survival, increased population growth, and consequent range expansion

Low population viability in small endangered orchid populations:genetic variation, seedling recruitment and stochasticity

Abstract There are only few studies that use both demographic and genetic data to assess population viability of plant species. We combined genetic and demographic data from 11 endangered perennial orchid populations of varying size in order to reveal determinants of viability. Small populations had substantially lower viability compared to large populations. Seedling recruitment rates were remarkably lower in small populations; this was not due to pollination limitation or inbreeding depression because the fruit set and heterozygosity were not correlated with population size, suggesting that there may be differences in successful germination. Low recruitment resulted in significantly lower predicted population growth rates in small populations. The impact of stochasticity on viability varied among populations and stochastic simulations indicated that only one large population was viable, whereas all the other large populations were predicted to go extinct within decades. While there was a positive correlation between the deterministic population growth rate and allelic richness, we did not find any other correlations between genetic variation and fitness or population size. The study populations are likely remnant populations of a once large meta-population that decreased in size due to unfavourable environmental conditions. Management should focus on the maintenance of large population size, which is needed to avoid negative consequences of stochasticity and to enhance seedling recruitment rates

The abundance of small mammals is positively linked to survival from nest depredation but negatively linked to local recruitment of a ground nesting precocial bird

Abstract Generalist predators using small mammals as their primary prey are suggested to shift hunting alternative prey such as bird nests, when small mammals are in short supply (the alternative prey hypothesis, APH). Nest survival and survival of young individuals should be positively linked to small mammal abundance and negatively linked to predator abundance, but little information exists from survival of chicks, especially until recruitment. We test these predictions of the APH using 13 years (2002–2014) of life history data from a ground nesting shorebird breeding on coastal meadows. We use small mammal abundance in the previous autumn as a proxy for spring predator abundance, mainly of mammalian predators. We examine whether small mammal abundance in the spring and previous autumn explain annual variation in nest survival from depredation and local recruitment of the southern dunlin Calidris alpina schinzii. As predicted by the APH, survival from nest predation was positively linked to spring small mammal abundance and negatively linked to autumn small mammal abundance. Importantly, local recruitment showed opposite responses. This counterintuitive result may be explained by density-dependent survival. When nest depredation rates are low, predators may show stronger numerical and functional responses to high shorebird chick abundance on coastal meadows, whereas in years of high nest depredation, few hatching chicks lure fewer predators. The opposite effects on nest and local recruitment demonstrate the diverse mechanisms by which population size variation in primary prey can affect dynamics of alternative prey populations

Absence of Francisella tularensis in Finnish Ixodes ricinus and Ixodes persulcatus ticks

Abstract Francisella tularensis subsp. holarctica is the causative agent of tularaemia in Europe. Finland is a high-incidence region for tularaemia, with mosquito bites as the most common sources of infection. However, in Central and Western Europe, ticks (Acari: Ixodidae) have been suggested as the main vectors. Indeed, several studies have reported the pathogen from the locally most common human-biting tick species, Ixodes ricinus. In Finland, the occurrence of the pathogen in ticks has started receiving attention only recently. Here, we collate previous tick screening data from Finland regarding F. tularensis as well as present the results from a novel screening of roughly 15 000 I. ricinus and I. persulcatus collected from across the country. In total, 14 878 ticks collected between 2015 and 2020 were screened for F. tularensis using a TaqMan-based qPCR assay targeting the 23 KDa gene. The combined screening efforts of the current and previous studies, encompassing roughly 20 000 ticks, did not find any positive ticks. Given the negative results despite the considerable sample size, it appears that the pathogen is not circulating in local tick populations in Finland. We discuss some possible reasons for the lack of the bacterium in ticks in this high-incidence region of tularaemia