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The article of record as published may be located at http://doi.org/10.1002/lno.10609 Surf zone hydrodynamics vary along shorelines potentially affecting the delivery of larvae and zooplankton subsidies to intertidal communities, and, hence, the intensity of postsettlement interactions, growth and reproduction of filter-feeding foundation species and planktivorous fishes. We investigated the ability of zooplankton assemblages to enter the wide surf zone of the rip-channeled, more dissipative beach at Sand City, California, and the narrow surf zone of the steep reflective beach at nearby Carmel River State Beach. Every day for a month, we surveyed zooplankton inside and outside the surf zone and concomitant larval settlement of the dominant invertebrate onshore at each site in this upwelling regime. At the more dissipative surf zone, all zooplankters were far more concentrated inside than outside the surf zone. Many taxa increased in the surf zone and the predominant invertebrate on beaches, Emerita analoga, settled abundantly when prevailing northwesterly winds relaxed and waves were small. At the reflective surf zone, concentrations of zooplankters of most taxa were far greater outside than inside the surf zone, and many taxa increased in the surf zone when waves were small. Twice as many taxa were positively correlated inside and outside the surf zone at the dissipative than the reflective surf zone, indicating that zooplankters were more freely exchanged although behavior also played a role. Thus, spatial and temporal variation in surf zone hydrodynamics may regulate subsidies of zooplankton food and larval recruits to nearshore communities with potential cascading effects on community dynamics and structure. Bodega Marine Laboratory and the Oregon Institute of Marine Biology NSF-OCE-0927196

© 2017 Blackwell Verlag GmbH Nearly all of our understanding of rocky inter-tidal ecology comes from studies conducted at low tide. To study inter-tidal organisms at high tide, we anchored waterproof digital GoPro®video cameras in wave-exposed tidepools and recorded the daytime movements of the black turban snail, Tegula funebralis, over the tidal cycle between May and August 2012 near Bodega Bay, California. Overall, snails moved more quickly and presumably foraged more during low tides and on days with warmer air and perhaps water temperatures. This is similar to other ectotherms that exhibit increased metabolic rates, movement and foraging in warmer conditions. Snails also moved less during flood and high tides, may have moved downward in tidepools at flood tides, and showed evidence of reduced activity on days with larger waves. This inactivity and refuge seeking may have been a strategy to avoid dislodgment by waves. Analysis of snail trajectories showed foraging bouts indicated by alternating zig-zagging and straight movement. There was no effect of temperature, wave height, or tidal phase on distribution of snail turning angles, suggesting that they may have foraged consistently but moved faster during warm conditions and low tides, thereby grazing a larger area. This is one of few direct recordings of inter-tidal organisms on wave-exposed rocky shores during high tide. The methods used here are easily transferable to other studies, which are needed to increase our understanding of behaviors that structure rocky shore communities during high tide.

© 2016 Liebowitz et al. Ecological connectivity can influence the distributions of diversity and productivity among ecosystems, but relationships among multiple marine ecosystems remain relatively uncharacterized. Sandy beaches are recipient ecosystems that support coastal food webs through deposits of drift macrophytes (wrack), and serve as test cases for exploring within-seascape connectivity. We present results from the first comprehensive survey of geographic and temporal patterns of wrack cover and composition on beaches along the North Central Coast of California and test the role of local donor ecosystems and physical factors in predicting wrack distribution. We surveyed wrack at 17 beaches in August 2010, and monthly at a subset of 10 beaches for 13 months. We estimated explanatory variables of (1) local donor ecosystem cover (kelp forests, rocky intertidal, and bays and estuaries), (2) biomass transport, and (3) beach morphology. Regression analyses were used to evaluate relationships among the cover of six key wrack categories and the explanatory variables above, for two time periods. We found persistent geographic variation in wrack composition and detected significant relationships between wrack cover and cover of local donor ecosystems for five of the six wrack categories (Nereocystis, Zostera, Postelsia, mixed red algae, and mixed brown algae). Transport mechanisms (wind exposure, swell exposure) or attributes of the recipient ecosystem (beach width, beach slope) explained additional spatial variation for three of the six wrack categories (Zostera, Phyllospadix, and mixed red algae). Our results support the concept of considering ecological connectivity (particularly the role of donor ecosystems upon which recipient ecosystems rely) in the design and management of protected areas.

Several studies on trait-mediated indirect interactions (TMIIs) have shown that predators can initiate trophic cascades by altering prey behaviour. Although it is well recognized that individual prey state alters antipredator and foraging behaviour, few studies explore whether this state-dependent prey behaviour can alter the strength of the ensuing tritrophic cascade. Here, we link state-dependent individual behaviour to community processes by experimentally testing whether hunger level and body size of prey altered antipredator behaviour and thus changed the strength of trophic cascades between predators and primary producers. In rocky intertidal tide pools on the California Coast, waterborne cues from the predatory seastar Leptasterias spp. (Stimpson) can cause the herbivorous snail Tegula (Chlorostoma) funebralis (A. Adams) to reduce grazing and flee tide pools, resulting in positive indirect effects on tide pool microalgae. However, we show that the strength of this behaviourally-mediated cascade may be contingent on prey hunger level and body size. During short field experiments at low tide, medium-sized snails that were either newly collected from the field or fed for 1�week in the laboratory mediated strong TMIIs because they grazed less when seastars were present. In contrast, no TMIIs occurred when medium-sized snails had been starved for 1�week because they continued grazing regardless of seastar presence. Newly collected small snails fled from seastars but did not mediate cascades because they ate little algae. Despite reaching an apparent size refuge from predation, many newly collected large snails fled from seastars, but those individuals that remained tended to graze the algae more quickly, resulting in unexpected negative indirect effects of seastars on algae cover. The implication of this pattern for the natural system is unclear. Because average hunger level and size of snails vary over time and space in nature, a mosaic of TMII strength may exist. Overall, the strength of tritrophic TMIIs in tide pools depended on individual prey state, supporting model predictions and adding to sparse empirical evidence. This outcome suggests that patterns occurring system-wide over the long term may be influenced by the state-dependent decisions made by the individuals present.

この論文では, 20世紀前半の学者と教育者, Boyd H. Bodeの目を通して教育心理学の分野を研究する。完全な要約が彼の本である'Conflicting theories of learning'(1929)とその改訂版の'How we learn'(1940)に載っている。その彼の論文での中心的な主張は, すばらしく明確な「心の理論」である。これは, 教育心理学の分野の研究者のみならず, 特に教育実践者の教師にも不可欠である。, This article explores the field of educational psychology as seen through the eyes of the early twentieth-century American scholar and pedagogue, Boyd H. Bode. A thorough summary is given of his book Conflicting theories of learning (1929) and its revised version How we learn (1940). The central thesis of his work is that having a well-articulated "theory of mind" is essential not only for researchers in the field of educational psychology, but especially for classroom teachers who are the actual practitioners of education.

Competent larvae of intertidal invertebrates have to migrate toward shore for settlement; however, their migration through the surf zone is not understood. We investigated larval transport mechanisms at a rip-channeled beach. Because tracking larvae in the surf zone is infeasible, we used a three-dimensional biophysical model to simulate the processes. The coupled model consists of a physical module for currents and waves, and a biological module for adding larval traits and behaviors as well as Stokes drift to Lagrangian particles. Model calculations were performed with and without onshore wind forcing. Without wind, wave-driven onshore streaming occurs in the bottom boundary layer outside the surf zone. With onshore wind, onshore currents occur near the surface. In the surf zone, offshore-directed rip currents and compensating onshore-directed currents over shoals are formed in both no-wind and wind cases. In the biological module, neutral, negative, and positive buoyant particles were released offshore. Additionally, particles either sank in the presence of turbulence or not. Two scenarios achieved successful onshore migration: Negatively buoyant larvae without wind forcing sink in the turbulent bottom boundary layer and are carried onshore by streaming; positively buoyant larvae drift toward shore in wind-driven surface currents to the surf zone, then sink in the turbulent surf zone and remain near the bottom while transported shoreward. In both cases, the larval concentration is highest in the rip channel, consistent with field data. This successful result is only obtained if turbulence-dependent sinking behavior and Stokes drift are included in the transport of larvae. © 2014, by the Association for the Sciences of Limnology and Oceanography, Inc.

Phenotypic plasticity is widespread in nature, and often involves ecologically relevant behavioral, physiological, morphological and life-historical traits. As a result, plasticity alters numerous interactions between organisms and their abiotic and biotic environments. Although much work on plasticity has focused on its patterns of expression and evolution, researchers are increasingly interested in understanding how plasticity can affect ecological patterns and processes at various levels. Here, we highlight an expanding body of work that examines how plasticity can affect all levels of ecological organization through effects on demographic parameters, direct and indirect species interactions, such as competition, predation, and coexistence, and ultimately carbon and nutrient cycles. © 2005 Elsevier Ltd. All rights reserved.

Estuarine crabs commonly display two larval dispersal patterns in which larvae are either exported from or retained within estuaries. Explanations for the disparate dispersal patterns are that larvae differ in their susceptibility to predation, which is greater within the estuary than offshore, or in their physiological tolerances to the large temperature and salinity fluctuations of the estuary. Crab larvae which are exported from the estuary survived better in stressful temperature and salinity combinations than those which are retained, and thus the physiological stress hypothesis was rejected. However, exported larvae were more vulnerable to predation by fishes and invertebrates than were retained larvae. The long spines, large body sizes and behavioral responses of retained crab larvae were more effective at deterring predation by two fishes and eleven invertebrates in the laboratory, than were the short spines and small body sizes of exported larvae. Spines generally were more effective against planktivorous fishes than against invertebrates. Spines operated by effectively increasing the size of the larvae and their unpalatability to fishes. Behavioral observations revealed that fishes repeatedly attacked zoeae, but would quickly learn to avoid the noxious prey. The armor of crab larvae enabled them to survive attacks, and fishes repeatedly attempting to swallow long-spined crab larvae frequently would die. Spines did not assist in the flotation or stabilization of crab larvae. Electivities of the three predominant fishes sampled from the Newport River estuary, North Carolina, also were greater for exported than retained species of crab larvae. Predation by larval and juvenile fishes was greater upstream compared to downstream, and greater diurnally than nocturnally. By hatching on nocturnal high tides, larvae rapidly disperse downstream where the probability of predation diminishes. Semiterrestrial crabs hatch on nocturnal spring tides to prevent stranding in tidal creeks. Thus, the hatching rhythms and dispersal patterns of crabs appear to have evolved in concert to transport larvae into coastal waters where the risk of predation is reduced, or to retain larvae within estuaries depending upon the vulnerability of the larva to predation.