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Animals of many different species, trophic levels, and life history strategies migrate, and the improvement of animal tracking technology allows ecologists to collect increasing amounts of detailed data on these movements. Understanding when animals migrate is important for managing their populations, but is still difficult despite modelling advancements. We designed a model that parametrically estimates the timing of migration from animal tracking data. Our model identifies the beginning and end of migratory movements as signaled by changes in step length and turning angle distributions. To this end, we can also use the model to estimate how an animal’s movement changes when it begins migrating. We tested our model on three datasets: migratory ferruginous hawks (Buteo regalis) in the Great Plains and barren-ground caribou (Rangifer tarandus groenlandicus) in northern Canada, and non-migratory brown bears (Ursus arctos) from the Canadian Arctic. We estimated the beginning and end of migration in caribou and hawks to the nearest day, while confirming a lack of migratory behaviour in the brown bear population. The flexibility of our modelling framework allowed us to assess intricacies associated with each dataset: long-term stopover behaviour in ferruginous hawks anda prioriknowledge of caribou calving areas and behaviour. In addition to estimating when caribou and ferruginous hawks migrated, our model also identified differences in how the two populations migrated; ferruginous hawks achieved efficient migrations by increasing their movement rates while caribou migration was achieved through significant increases in directional persistence. Our approach is broadly applicable to many animal movement studies. We anticipate that rigorous assessment of migration metrics will aid understanding of both how and why animals move.

Passive integrated transponder (PIT) tags allow a range of individual‐level data to be collected passively and have become a commonly used technology in many avian studies. Although the potential adverse effects of PIT tags have been evaluated in several species, explicit investigations of their impacts on small (, We investigated lethal (mortality) and nonlethal (body condition) effects of different two PIT tagging methods (implants or leg band embedded) compared with birds that were color banded but not fitted with PIT tags. In a sample of over 200 birds followed for more than two years, we found no evidence of differences in survival or body condition across any of these three treatments.

Designing an effective conservation strategy requires understanding where rare species are located. Because rare species can be difficult to find, ecologists often identify other species called conservation surrogates that can help inform the distribution of rare species. Species distribution models typically rely on environmental data when predicting the occurrence of species, neglecting the effect of species' co‐occurrences and biotic interactions. Here, we present a new approach that uses Bayesian networks to improve predictions by modeling environmental co‐responses among species. For species from a European peat bog community, our approach consistently performs better than single‐species models and better than conventional multi‐species approaches that include the presence of nontarget species as additional independent variables in regression models. Our approach performs particularly well with rare species and when calibration data are limited. Furthermore, we identify a group of “predictor species” that are relatively common, insensitive to the presence of other species, and can be used to improve occurrence predictions of rare species. Predictor species are distinct from other categories of conservation surrogates such as umbrella or indicator species, which motivates focused data collection of predictor species to enhance conservation practices., It is difficult to protect rare species from extinction because of their sparse distributions and specialized habitat preferences. Here, we use Bayesian networks to accurately predict the occurrence of rare species, providing a solution to an ever‐important conservation problem.

Animal learning has interested ecologists and psychologists for over a century. Mathematical models that explain how animals store and recall information have gained attention recently. Central to this work is statistical decision theory (SDT), which relates information uptake in animals to Bayesian inference. SDT effectively explains many learning tasks in animals, but extending this theory to predict how animals will learn in changing environments still poses a challenge for ecologists. We addressed this shortcoming with a novel implementation of Bayesian Markov Chain Monte Carlo (MCMC) sampling to simulate how animals sample environmental information and learn as a result. We applied our framework to an individual-based model simulating complex foraging tasks encountered by wild animals. Simulated ``animals" learned behavioral strategies that optimized foraging returns simply by following the principles of an MCMC sampler. In these simulations, behavioral plasticity was most conducive to efficient foraging in unpredictable and uncertain environments. Our model suggests that animals prioritize highly concentrated resources even when these resources are less available overall, in line with existing knowledge on optimal foraging and ideal free distribution theory. Our innovative computational modelling framework can be applied more widely to simulate the learning of many other tasks in animals and humans., Comment: 6 figures, 1 table, 2 figures in the supplementary material

1. Spatial memory plays a role in the way animals perceive their environments, resulting in memory-informed movement patterns that are observable to ecologists. Developing mathematical techniques to understand how animals use memory in their environments allows for an increased understanding of animal cognition. 2. Here we describe a model that accounts for the memory of seasonal or ephemeral qualities of an animal's environment. The model captures multiple behaviors at once by allowing for resource selection in the present time as well as long-distance navigations to previously visited locations within an animal's home range. 3. We performed a set of analyses on simulated data to test our model, determining that it can provide informative results from as little as one year of discrete-time location data. We also show that the accuracy of model selection and parameter estimation increases with more location data. 4. This model has potential to identify a specific mechanism in which animals use memory to optimize their foraging, by revisiting temporally and predictably variable resources at consistent time lags., 23 pages, including title and abstract; 4 tables; 3 figures; one Appendix containing 2 additional tables and 1 additional figure

Spatial memory plays a role in the way animals perceive their environments, re-sulting in memory-informed movement patterns that are observable to ecologists. Developing mathematical techniques to understand how animals use memory in their environments allows for an increased understanding of animal cognition. Here we describe a model that accounts for the memory of seasonal or ephem-eral qualities of an animal's environment. The model captures multiple behaviours at once by allowing for resource selection in the present time as well as long- distance navigations to previously visited locations within an animal's home range. We performed a set of analyses on simulated data to test our model, determin-ing that it can provide informative results from as little as 1 year of discrete-time location data. We also show that the accuracy of model selection and parameter estimation increases with more location data. This model has potential to identify a specific mechanism in which animals use memory to optimize their foraging, by revisiting temporally and predictably vari-able resources at consistent time- lags.

Designing an effective conservation strategy requires understanding where rare species are located. Although species distribution models are primarily used to identify patterns at large spatial scales, their general methodology is relevant for predicting the occurrence of individual species at specific locations. Here we present a new approach that uses Bayesian networks to improve predictions by modelling environmental co-responses among species. For species from a European peat bog community, our approach consistently performs better than single-species models, and better than conventional multi-species models for rare species when calibration data are limited. Furthermore, we identify a group of “predictor species” that are relatively common, insensitive to the presence of other species, and can be used to improve occurrence predictions of rare species. Predictor species are distinct from other categories of conservation surrogates such as umbrella or indicator species, which motivates focused data collection of predictor species to enhance conservation practices.

A Pb(Zr,Ti)O 3 precursor gel made from a sol prepared using 1,1,1,-tris(hydroxymethyl)ethane, lead acetate and zirconium and titanium propoxides, stabilised with acetylacetone, was analysed using TGA–FTIR analysis. Decomposition under nitrogen (N 2 ) gave rise to evolved gas absorbance peaks at 215 °C, 279 °C, 300 °C and 386 °C, but organic vapours continued to be evolved, along with CO 2 and CO until ∼950 °C. The final TGA step in N 2 is thought to relate to decomposition of an intermediate carbonate phase and the final elimination of residues of triol or acetylacetonate species which form part of the polymeric gel structure. By contrast, heating in air promoted oxidative pyrolysis of the final organic groups at ≤450 °C. In air, an intermediate carbonate phase was decomposed by heating at ∼550 °C, allowing Pb(Zr,Ti)O 3 to be produced some 400 °C below the equivalent N 2 decomposition temperature.

Exploration of the Haynesville and Bossier shale play in east Texas and western Louisiana provides an opportunity for many onshore-focused, U.S. geoscientists to reacquaint themselves with biostratigraphy. Using both vintage and new biostratigraphic data, this study showcases the integration of multiple biostratigraphic disciplines for (1) identification of unique correlation surfaces within the basin; (2) increased resolution and confidence in the age assignments for surfaces defined by logs and seismic; and (3) the recognition of distinct biofacies, which aid in the prediction of preferred intervals and geographic areas for hydrocarbon accumulation within shales. This study incorporates interpretations from five wells using nannofossils, foraminifera, ammonites, and radiolarians. The strengths and weaknesses of each fossil discipline are discussed in the context of a multidisciplinary stratigraphic evaluation. Rock materials for the study were collected from both cuttings and core from stratigraphic intervals interpreted as Haynesville Shale, Bossier Shale, Taylor Sands, and Cotton Valley Group siliciclastics. Biostratigraphic interpretations, which range from lower Kimmeridgian to lower Berriasian, establish more accurate and reliable timelines than have previously been published from a Jurassic basin in North America. Complementing the age interpretations, four key biofacies are recognized and mapped. Some of the biofacies are interpreted to be associated with significant dysoxic to anoxic bottom conditions and potentially areas of corresponding elevated surface productivity, whereas others likely represent changes in sediment supply into the basin from nearby terrigenous clastic and/or detrital carbonate sources.

Eocene to Oligocene marine carbonate shelf deposits in a continuous core in Baldwin County, Alabama, were evaluated within a sequence stratigraphic framework to determine characteristic stable isotopic responses to inferred fluctuations in sea level. Due to a greater sampling density per unit of time, stable isotopes in this core reveal more defined trends than have previously been reported from DSDP/ODP (Deep Sea Drilling Project/Ocean Drilling Project) records and from more land-ward sections that have undergone intense sub-aerial alteration or erosion. The δ 18 O signature records eustatic sea level. δ 18 O becomes heavier as eustatic sea level falls and lighter as eustatic sea level rises. δ 18 O records a secular shift to heavy from the early Eocene to Oligocene of 3.0‰. The δ 13 C signature records relative sea-level change (paleobathymetry). δ 13 C generally becomes heavier in shallower water deposits and lighter in deeper water deposits. However, in planktonic oozes, δ 13 C may shift to heavy. δ 13 C also records a secular shift to heavy from the early Eocene to the Oligocene of 3.5‰ Although minor diagenetic perturbations in the stable isotopes are present, the depositional signal dominates the isotopic signal. Spar cements generally result in lighter δ 18 O and δ 13 C. If the dolomite is >20% dolomitization results in heavier δ 18 O and δ 13 C.

The Finisterre Mountains of northern Papua New Guinea are the site of an active, southeast-propagating collision between the Finisterre terrane and the Australian continental margin. The clastic sedimentary sequence on the southern flank of the range records the history of the collision. The age of initial collision can be deduced from the second of two provenance shifts that occur in the sequence, as revealed by a study of 69 dated sandstones. The first shift, at about 16-18 Ma, was from volcanolithic sediments to mixed-provenance sediments rich in quartz and metasedimentary lithic fragments. These latter sediments were probably derived from the orogenic belt active along the Australian continental margin at that time. At 3.0-3.7 Ma the volcanic source was rejuvenated. Initial collis on at this time uplifted the Finisterre terrane, causing the provenance shift. Here we break the stratigraphic sequence into three units: the Sarawaget beds, the Erap Structural Complex, and the Leron Formation. The Sarawaget beds are Middle Eocene to Early Miocene volcanolithic sandstones that were deposited as clastic aprons un the flanks of the Finisterre volcanic are. Volcanic activity ceased in the Early Miocene. The Erap Complex is divided into two clastic subunits, the Sukurum and Nariawang units, and one basaltic subunit, the Gorambampan unit. The Sukurum unit consists of turbidites deposited south of the extinct Finisterre Arc from the latest Early Miocene through the Early Pliocene. Much of the sediment in the unit was derived from low- to medium-grade metasedimentary units on the active northern margin of the Australian continent. Renewed subduction i the Late Miocene or Pliocene occurred along the New Britain Trench, just south of the remnant Finisterre Arc, closing an eastward-widening small ocean basin. The Sukurum unit probably represents an accretionary prism that formed at this subduction zone. Scattered seamounts that were scraped off the downgoing plate are preserved as the Gorambampan unit. Initial collision of the Finisterre terrane with the continental margin at 3.0-3.7 Ma uplifted the Paleogene volcanic rocks, which were rapidly eroded and deposited as the volcanolithic turbidites of the Nariawang unit. Southeastward propagation of the collision tip caused incorporation of the Nariawang unit into the accretionary wedge. Rapid uplift raised the terrane foreland above sea level sometime after 1.3 Mo. The fluvial, lacustrine and marginal-marine deposits of the Leron Formation accumulated in a terrane foreland basin that developed south of the collision zone. Further propagation of the thrust front toward the foreland incorporated the Leron Formation into the fold-and-thrust belt. Rapid uplift of the Finisterre Range and voluminous volcanolithic sedimentation continue to the present. In the Finisterre Range, arc-continent collision is marked by a provenance shift from metasedimentary and quartzose detritus to volcanic detritus. In another modern arc-continent collision on Taiwan, collision has caused a shift from volcanic to metasedimentary detritus. We attribute this discrepancy to the presence of the Finisterre terrane, an extinct arc, in the forearc region of the Finisterre arc-continent collision and the absence of a similar terrane in the forearc area on Taiwan. The very different evolution of sandstone provenance in the active Taiwan and Finisterre collision zones shows that local factors can profoundly influence the provenance histories of collision zones. No one model of sediment provenance evolution can characterize all collision zones, whether modern or ncient.

Intraspecific coiling variations of the planktonic foraminifer Neogloboquadrina pachyderma (Ehrenberg) form an important micropalaeontological technique for the palaeoclimatic interpretation of late Cenozoic mid-latitude marine sediments. In all the modern oceans, this species preferentially coils dextrally in subtropical to temperate latitudes and sinistrally in subpolar to polar latitudes1,2. Plankton3–5 and surface sediment studies6–20 of the North Pacific clearly associate sinistral populations with subarctic water masses and dextral populations with temperate subtropical regions. Here we show that down-core ratios of sinistral to dextral coiling, when correlated with oxygen isotopes, indicate major late Quaternary southward advances of the subarctic boundary (polar front) and the Oyashio Current during oxygen isotope stages 2,4 and 6.

Faunal census data on zooplankton microfossils in surface sediment samples are treated by Q-mode factor analysis and are used to describe the global distributions of five faunal provinces: the polar, subpolar, transitional-subtropical, and eastern and western tropical provinces. The same assemblages (factors) are used to describe and to map equivalent faunal provinces in the ice-age ocean (18 000 B.P.; CLIMAP 1976 1981). Although based on individual studies in each ocean basin, the compilation of these data on different faunal groups allows a clear comparison of water mass distributions in the modern and ice-age oceans. This comparison shows an expansion of the polar province, an equatorward shift and compression of the subpolar and transitional-subtropical provinces, and an extension of the subpolar province equatorward in eastern boundary currents for the ice-age interval. The total area of dominance for the tropical and subpolar assemblages remained approximately constant. Comparison of census data between surface sediment and 18 000 B.P. samples shows that the greatest faunal change occurred near the subpolar regions (where water mass boundaries shifted equatorward) and in areas of expanded upwelling and divergence (primarily eastern boundary currents and eastern equatorial areas). In contrast, little faunal change occurred either in the polar regions or within the central subtropical gyres.

A 120 m thick section of the Cozy Dell Formation (middle Eocene), southem California, consists of a graylaminated mudstone and a tanungraded mudstone; sandstone beds are associated with the laminated mudstone. Sedimentary structures, stratification sequences, foraminiferal distributions, and composition indicate that the ungraded mudstone is an upper slope hemipelagic deposit, while the laminated mudstone is an overbank deposit associated with shallow channels or gullies in which the sandstone beds were deposited. This depositional setting may be analogous to that of the modern Mississippi River delta front.

The Upper Cretaceous (Campanian) Kenilworth Member of the Blackhawk Formation (Mesaverde Group) is part of a series of strand plain sandstones that intertongue with and overstep the shelfal shales of the western interior basin of North America. Analysis of this section at a combination of small (sedimentological) and large (stratigraphical) scales reveals the dynamics of progradation of a shelf-slope sequence into a subsiding foreland basin. Four major lithofacies are present in the upper Mancos and Kenilworth beds of the Book Cliffs. A lag sandstone and channel-fill shale lithofacies constitutes the thin, basal, transgressive sequence, which rests on a marine erosion surface. It was deposited in an outer shelf environment. Shale, interbedded sandstone and shale, and amalgamated sandstone lithofacies were deposited over the transgressive lag sandstone lithofacies as a wave-dominated delta and its flanking strand plains prograded seaward. Analysis of grain size and primary structures in Kenilworth beds indicates that there are four basic strata types which combine to build the observed lithofacies. The fine- to very fine-grained graded strata of the interbedded facies are tempestites, deposited out of suspension by alongshelf storm flows (geostrophic flows). There is no need to call on cross-shelf turbidity currents (density underflows) to explain their presence. Very fine- to fine-grained hummocky strata are likewise suspension deposits created by waning storm flows, but were deposited under conditions of more intense wave agitation on the middle shoreface. Cross-strata sets in this region are bed-load deposits that accumulated on the upper shore-face, in the surf zone. Lag strata are multi-event, bed-load deposits that are the product of prolonged storm winnowing. They occur on transgressive surfaces. While the graded beds are tempestites in the strict sense, all four classes of strata are storm deposits. The distribution of strata types and their palaeocurrent orientations suggests a model of the Kenilworth transport system driven by downwelling coastal storm flows, and probably by a northeasterly alongshore pressure gradient. The stratification patterns shift systematically from upper shoreface to lower shoreface and inner shelf lithofacies partly because of a reduction in fluid power expenditure with increasing water depth, but also because of progressive sorting, which resulted in a decrease in grain size in the sediment load delivered to successive downstream environments. The Kenilworth Member and an isolated outlier, the Hatch Mesa lentil, constitute a delta-prodelta shelf depositional system. Their rhythmically bedded, lenticular, sandstone and shale successions are a prodelta shelf facies, and may be prodelta plume deposits. Major Upper Cretaceous sandstone tongues in the Book Cliffs are underlain by erosional surfaces like that beneath the Blackhawk Formation, which extend for many tens of kilometres into the Mancos shale. These surfaces are the boundaries of Upper Cretaceous depositional sequences. The sequences are large-scale genetic stratigraphic units. They result from the arranging of facies into depositional systems; the depositional systems are in turn stacked in repeating arrays, which constitute the depositional sequences. The anatomy of these foreland basin sequences differs

Planktonic foraminiferal datums for the Pleistocene of the Equatorial Pacific have frequently been shifted vertically by dissolution and bioturbation. Evolutionary initial appearances and final extinctions are altered to first and last lithostratigraphic occurrences, respectively. Shallow cores with high sedimentation rates are least affected by these processes and provide the most reliable chronostratigraphic resolution. Ten datum levels are proposed for the Quaternary and five for the latest Pliocene, all of which have been dated by palaeomagnetic stratigraphy.

International audience; The final effort of the CLIMAP project was a study of the last interglaciation, a time of minimum ice volume some 122,000 yr ago coincident with the Substage 5e oxygen isotopic minimum. Based on detailed oxygen isotope analyses and biotic census counts in 52 cores across the world ocean, last interglacial sea-surface temperatures (SST) were compared with those today. There are small SST departures in the mid-latitude North Atlantic (warmer) and the Gulf of Mexico (cooler). The eastern boundary currents of the South Atlantic and Pacific oceans are marked by large SST anomalies in individual cores, but their interpretations are precluded by no-analog problems and by discordancies among estimates from different biotic groups. In general, the last interglacial ocean was not significantly different from the modern ocean. The relative sequencing of ice decay versus oceanic warming on the Stage 6/5 oxygen isotopic transition and of ice growth versus oceanic cooling on the Stage 5e/5d transition was also studied. In most of the Southern Hemisphere, the oceanic response marked by the biotic census counts preceded (led) the global ice-volume response marked by the oxygen-isotope signal by several thousand years. The reverse pattern is evident in the North Atlantic Ocean and the Gulf of Mexico, where the oceanic response lagged that of global ice volume by several thousand years. As a result, the very warm temperatures associated with the last interglaciation were regionally diachronous by several thousand years. These regional lead-lag relationships agree with those observed on other transitions and in long-term phase relationships; they cannot be explained simply as artifacts of bioturbational translations of the original signals.

The planktonic foraminiferal species Globigerinoides ruber with pink-pigmented tests occupied a worldwide warm-water belt during much of the Pleistocene. This variety was exterminated from the Indian and Pacific Oceans at about 120,000 yr BP, based on the oxygen isotope stratigraphy in 11 Indo-Pacific deep-sea cores, but it continued to live on to the present in the North and South Atlantic Ocean and the Mediterranean Sea. The disparate Atlantic and Indo-Pacific records reflect faunal provincialism that has been developing in the two regions since the Pliocene.

Drill cores from a transect of the Mid-America Trench off Guatemala were obtained at three sites on the oceanic Cocos plate, and at four sites on the continental Caribbean plate. An ocean sub-bottom seismometer was successfully emplaced in the deepest hole in the trench landward slope where it was left to record data after departure of the drill ship. Drilling on the Cocos plate recovered a basal chalk sequence deposited during early and mid-Miocene time, a short interval of abyssal red clay, and an upper sequence of late Miocene and younger sediment deposited within an area influenced by a terrigenous source. In the trench, a mud and sand fill less than 400,000 yr old overlies the oceanic sequence. The entire section shows no evidence of compressive deformation even at holes drilled against the trench9s landward slope. In contrast, the section cored on the trench9s landward slope 3 km from the trench axis is affected by tectonism. The section contains a Cretaceous to Pliocene claystone sequence, broken by hiatuses but in a normal stratigraphic succession that is capped by Pliocene to Quaternary hemipelagic slope deposits. Seismic records show that the section overlies probable igneous oceanic crust from which it is separated by a few hundred metres. That thickness of undrilled section is insufficient to accommodate the potential offscraped volume of oceanic sediment carried into the trench during Neogene plate convergence. At the estimated 10 cm/yr rate of convergence, much of the oceanic sediment must have been subducted rather than tectonically accreted to the Guatemalan margin. Current models for convergent margin tectonics do not satisfactorily explain the surprising occurrence of Cretaceous to Miocene mudstone at the base of this trench slope. The recovery of gas hydrates prevented drilling to some landward-dipping reflections presumed to be imbricate thrust slices at two sites near the middle of the trench landward slope.

Late Pleistocene equatorial Pacific sediments can be correlated by the ratios of certain solution-susceptible versus solution-resistant planktonic foraminifera. These ratios fluctuate in a cyclic manner whose timing is in phase with glacial-interglacial fluctuations established by oxygen isotope geo-chronology. Glacial stages are characterized by less solution of foraminifera than interglacial stages.

Neoacarinina blowi n. gen., n. sp., Globorotalia crozetensis n. sp. may be useful datum for Pleistocene/Holocene boundary