Aerial Inventories of Waterfowl in Illinois and Estimation of Moist-soil Plant Seed Abundance for Waterfowl on Lands Managed by Illinois Department of Natural Resources

Grant/Contract No: W-43-R 53-54-55Reports on progress and results of inventories of waterfowl along the Illinois and central Mississippi rivers during fall and winter and estimation of moist-soil plant seed abundance for waterfowl on lands managed by Illinois Department of Natural ResourcesINHS Technical Report Prepared for U.S. Fish & Wildlife Service, Illinois Department of Natural Resource

Waterbird and Wetland Monitoring at The Emiquon Preserve Final Report 2007-2009

We monitored the response of wetland habitats and waterbirds to restoration efforts at Emiquon during 2007–2010 to evaluate restoration success relative to desired conditions under the relevant key ecological attributes (KEAs). Our primary efforts included evaluating: 1) abundance, diversity, and behavior of waterfowl and other waterbirds through counts and observations; 2) productivity by waterfowl and other waterbirds through brood counts; 3) plant seed and invertebrate biomass to understand foraging carrying capacity for waterfowl during migration and breeding, and; 4) composition and arrangement of the vegetation community through geospatial wetland covermapping. Herein, we report results of our monitoring efforts and interpret them as a means of evaluating restoration activities at Emiquon with respect to desired conditions under the KEAs.The Nature Conservancy, Illinois River Project Office, contract number C07-032unpublishednot peer reviewedOpe

Feeling Small: Exploring the Tactile Perception Limits

The human finger is exquisitely sensitive in perceiving different materials, but the question remains as to what length scales are capable of being distinguished in active touch. We combine material science with psychophysics to manufacture and haptically explore a series of topographically patterned surfaces of controlled wavelength, but identical chemistry. Strain-induced surface wrinkling and subsequent templating produced 16 surfaces with wrinkle wavelengths ranging from 300 nm to 90 μm and amplitudes between 7 nm and 4.5 μm. Perceived similarities of these surfaces (and two blanks) were pairwise scaled by participants, and interdistances among all stimuli were determined by individual differences scaling (INDSCAL). The tactile space thus generated and its two perceptual dimensions were directly linked to surface physical properties – the finger friction coefficient and the wrinkle wavelength. Finally, the lowest amplitude of the wrinkles so distinguished was approximately 10 nm, demonstrating that human tactile discrimination extends to the nanoscale

Seed Abundance for Waterfowl in Wetlands Managed by the Illinois Department of Natural Resources

Managed wetlands on public lands in Illinois, United States, provide foraging habitats for migrating and wintering waterfowl. However, few studies have estimated abundances of waterfowl foods in mid-migration regions of North America, yet such information is needed to inform management and conservation decision-making. During 2005– 2007, we used a multistage sampling design to estimate moist-soil plant seed production (kg/ha, dry mass) and energetic carrying capacity at sites managed by the Illinois Department of Natural Resources and modeled variation in seed biomass. Average seed biomass among all sites ranged from 1,030.0 6 64.1 (SE) kg/ha in 2005 to 501.5 6 124.1 kg/ha in 2007. Our overall estimate (2005–2007) of moist-soil plant seed biomass was precise (691.3 6 56.4 kg/ ha; CV: 8.2%), equaling 5,128 energetic use-days/ha. This value was similar to or slightly greater than previous estimates from other regions of North America and exceeded the estimate used the Upper Mississippi River and Great Lakes Region Joint Venture for waterfowl conservation planning (514 kg/ha). We formulated eight models to predict abundance of moist-soil plant seeds within sampled wetlands. The best approximating model included the number of desirable plant species within wetlands and study year. The second best model included the categorical effect of management intensity and indicated that, although variable, actively managed wetlands produced about 240 kg/ha more seed than those that were passively managed. As with other regions, wetland management practices that encourage diverse plant communities over monotypes and growth of early successional plants should yield substantial increases in waterfowl food abundances at Illinois Department of Natural Resources sites, especially given that only 27% of our study wetlands were actively managed. Such efforts would also help reduce deficits in energetic carrying capacity identified by the Upper Mississippi River and Great Lakes Region Joint Venture

Foraging Ecology of Fall-Migrating Shorebirds in the Illinois River Valley

Populations of many shorebird species appear to be declining in North America, and food resources at stopover habitats may limit migratory bird populations. We investigated body condition of, and foraging habitat and diet selection by 4 species of shorebirds in the central Illinois River valley during fall migrations 2007 and 2008 (Killdeer [Charadrius vociferus], Least Sandpiper [Calidris minutilla], Pectoral Sandpiper [Calidris melanotos], and Lesser Yellowlegs [Tringa flavipes]). All species except Killdeer were in good to excellent condition, based on size-corrected body mass and fat scores. Shorebird diets were dominated by invertebrate taxa from Orders Diptera and Coleoptera. Additionally, Isopoda, Hemiptera, Hirudinea, Nematoda, and Cyprinodontiformes contribution to diets varied by shorebird species and year. We evaluated diet and foraging habitat selection by comparing aggregate percent dry mass of food items in shorebird diets and core samples from foraging substrates. Invertebrate abundances at shorebird collection sites and random sites were generally similar, indicating that birds did not select foraging patches within wetlands based on invertebrate abundance. Conversely, we found considerable evidence for selection of some diet items within particular foraging sites, and consistent avoidance of Oligochaeta. We suspect the diet selectivity we observed was a function of overall invertebrate biomass (51.264.4 [SE] kg/ha; dry mass) at our study sites, which was greater than estimates reported in most other food selection studies. Diet selectivity in shorebirds may follow tenants of optimal foraging theory; that is, at low food abundances shorebirds forage opportunistically, with the likelihood of selectivity increasing as food availability increases. Nonetheless, relationships between the abundance, availability, and consumption of Oligochaetes for and by waterbirds should be the focus of future research, because estimates of foraging carrying capacity would need to be revised downward if Oligochaetes are truly avoided or unavailable for consumption

Foraging Thresholds of Spring Migrating Dabbling Ducks in Central Illinois

The Upper Mississippi River and Great Lakes Region Joint Venture (hereafter, JV) endeavors to model energetic carrying capacity to inform conservation planning in the JV region. Currently, carrying capacity models use estimates of food production (e.g., moist-soil plant seeds) and habitat availability (area). However, estimates of the amount of food exploited by ducks with respect to availability are lacking. The JV currently assumes a conservative foraging threshold of 50% of gross food abundance can be exploited by foraging ducks. Giving-up densities (GUDs), which express the amount of food that remains after organisms cease foraging, can be used to estimate foraging thresholds. We endeavored to provide information to refine the JV’s foraging-threshold estimate through field experiments. We used experimental foraging patches, placed in wetlands used by spring-migrating dabbling ducks (Anas spp.) along the central Illinois River valley (IRV), to estimate the GUD in relation to experimentally manipulated seed density, seed size, seed depth in the substrate, substrate type, and predation risk. We conducted 7 foraging trials in 2010(March and April) and 10 in 2011(February–April), beginning immediately following spring ice-out. Trials were comprised of a series of plastic pans (foraging patches) filled with a combination of substrate (e.g., sand, clay) and seed (Japanese millet and red rice) and placed in wetlands near dabbling duck concentration areas. We monitored trial plots daily for duck use and conducted behavioral observations of ducks near trial plots. Once plots were abandoned by foraging ducks, we removed experimental patches, sorted seed from substrate, and dried and weighed remaining seed to estimate the GUD. Our results differed greatly between years. We had difficulty attracting ducks to trial plots in 2010, and use and seed exploitation was correspondingly low. On average, 521.4kg/ha (20%removed) of seed remained following duck abandonment in 2010. We had greater success attracting ducks to plots in 2011, and this was reflected by lower average GUD(35.8kg/ha, 94% removed). Ducks foraged more efficiently in sand than clay substrates, and better exploited shallowly buried over deeply buried seeds; however, we only collected data on the latter in 2010. Initial seed density decreased the GUD in 2010, but not in 2011, whereas predation risk increased the GUD in 2011 but not in 2010. Finally, ducks favored small seeds in 2010, but large seeds in 2011. Although our annual results contrasted, several of these differences may be explained by foraging theory and variation in migration chronology. Indeed, local food abundance likely varied considerably between years. Other food sources represent missed opportunities to ducks; thus, we expect the GUD to vary with respect to missed opportunity costs. When missed opportunity costs are high(i.e., high local food abundance outside of our test plots), the GUD in experimental patches should be correspondingly high, whereas the GUD will be lower when missed opportunity costs are also lower(i.e., relatively low local food abundance). Additionally, ice-out was nearly 1 month later than average (15 March) in 2010, and approximately average (15 February) in 2011. This difference may have shortened the stopover duration of large-bodied dabbling ducks (e.g., mallard [Anas platyrhynchos]) at our study sites, potentially altering the GUDs. Despite these interannual differences, our results demonstrate that ducks can remove substantially more seed from wetland habitats than the estimate currently used by the JV. Therefore, we suggest the JV consider incorporating the GUD estimates generated by this study into future energetic carrying capacity models. However, revising carrying capacity models would lead to revision of habitat protection and enhancement goals and should be approached cautiously. Perhaps carrying capacity estimates based on the results of our study could be considered as alternate or competing models to the current approach. In this scenario, consideration of formally revising the estimates based on lowered foraging thresholds might be framed in the context of adaptive resource management, whereby support for formal revision could be based on the weight of evidence as our study is replicated or results otherwise supported or refuted.unpublishednot peer reviewedOpe

Inter-annual decrease in pulse rate and peak frequency of Southeast Pacific blue whale song types

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Malige, F., Patris, J., Buchan, S. J., Stafford, K. M., Shabangu, F., Findlay, K., Hucke-Gaete, R., Neira, S., Clark, C. W., & Glotin, H. Inter-annual decrease in pulse rate and peak frequency of Southeast Pacific blue whale song types. Scientific Reports, 10(1), (2020): 8121, doi:10.1038/s41598-020-64613-0.A decrease in the frequency of two southeast Pacific blue whale song types was examined over decades, using acoustic data from several different sources in the eastern Pacific Ocean ranging between the Equator and Chilean Patagonia. The pulse rate of the song units as well as their peak frequency were measured using two different methods (summed auto-correlation and Fourier transform). The sources of error associated with each measurement were assessed. There was a linear decline in both parameters for the more common song type (southeast Pacific song type n.2) between 1997 to 2017. An abbreviated analysis, also showed a frequency decline in the scarcer southeast Pacific song type n.1 between 1970 to 2014, revealing that both song types are declining at similar rates. We discussed the use of measuring both pulse rate and peak frequency to examine the frequency decline. Finally, a comparison of the rates of frequency decline with other song types reported in the literature and a discussion on the reasons of the frequency shift are presented.The authors thank the help of Explorasub diving center (Chile), Agrupación turística Chañaral de Aceituno (Chile), ONG Eutropia (Chile), Valparaiso university (Chile), the international institutions and research programs CTBTO, IWC, BRILAM STIC AmSud 17-STIC-01. S.J.B. thanks support from the Center for Oceanographic Research COPAS Sur-Austral, CONICYT PIA PFB31, Biology Department of Woods Hole Oceanographic Institution, the Office of Naval Research Global (awards N62909-16-2214 and N00014-17-2606), and a grant to the Centro de Estudios Avanzados en Zonas Ãridas (CEAZA) “Programa Regional CONICYT R16A10003”. We thank SABIOD MI CNRS, EADM MaDICS CNRS and ANR-18-CE40-0014 SMILES supporting this research. We are grateful to colleagues at DCLDE 2018 and SOLAMAC 2018 conferences for useful comments on the preliminary version of this work. In this work we used only the free and open-source softwares Latex, Audacity and OCTAVE

Investigating decision rules with a new experimental design: the EXACT paradigm.

In the decision-making field, it is important to distinguish between the perceptual process (how information is collected) and the decision rule (the strategy governing decision-making). We propose a new paradigm, called EXogenous ACcumulation Task (EXACT) to disentangle these two components. The paradigm consists of showing a horizontal gauge that represents the probability of receiving a reward at time t and increases with time. The participant is asked to press a button when they want to request a reward. Thus, the perceptual mechanism is hard-coded and does not need to be inferred from the data. Based on this paradigm, we compared four decision rules (Bayes Risk, Reward Rate, Reward/Accuracy, and Modified Reward Rate) and found that participants appeared to behave according to the Modified Reward Rate. We propose a new way of analysing the data by using the accuracy of responses, which can only be inferred in classic RT tasks. Our analysis suggests that several experimental findings such as RT distribution and its relationship with experimental conditions, usually deemed to be the result of a rise-to-threshold process, may be simply explained by the effect of the decision rule employed