[MARMAM] New publication: Three decades of gray whale habitat use, distribution, and abundance

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to share our recent publication in 
Scientific Reports:

Barlow, D.R., Strong, C.S. & Torres, L.G. Three decades of nearshore surveys 
reveal long-term patterns in gray whale habitat use, distribution, and 
abundance in the Northern California Current. Sci Rep 14, 9352 (2024). 
https://doi.org/10.1038/s41598-024-59552-z

ABSTRACT: The nearshore waters of the Northern California Current support an 
important seasonal foraging ground for Pacific Coast Feeding Group (PCFG) gray 
whales. We examine gray whale distribution, habitat use, and abundance over 31 
years (1992–2022) using standardized nearshore (< 5 km from shore) surveys 
spanning a large swath of the PCFG foraging range. Specifically, we generated 
density surface models, which incorporate detection probability into 
generalized additive models to assess environmental correlates of gray whale 
distribution and predict abundance over time. We illustrate the importance of 
coastal upwelling dynamics, whereby increased upwelling only yields higher gray 
whale density if interspersed with relaxation events, likely because this 
combination optimizes influx and retention of nutrients to support recruitment 
and aggregation of gray whale prey. Several habitat features influence gray 
whale distribution, including substrate, shelf width, prominent capes, and 
river estuaries. However, the influence of these features differs between 
regions, revealing heterogeneity in habitat preferences throughout the PCFG 
foraging range. Predicted gray whale abundance fluctuated throughout our study 
period, but without clear directional trends, unlike previous abundance 
estimates based on mark-recapture models. This study highlights the value of 
long-term monitoring, shedding light on the impacts of variable environmental 
conditions on an iconic nearshore marine predator.

The full article is open access, and available online: 
https://www.nature.com/articles/s41598-024-59552-z

Please do not hesitate to reach out with any questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow, PhD (she/her)
Postdoctoral Scholar
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Variation in blue whale morphology across three productive coastal ecosystems

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to share our recent paper in 
Integrative Organismal Biology:

D R Barlow, K C Bierlich, W K Oestreich, G Chiang, J W Durban, J A Goldbogen, D 
W Johnston, M S Leslie, M J Moore, J P Ryan, L G Torres, Shaped by Their 
Environment: Variation in Blue Whale Morphology across Three Productive Coastal 
Ecosystems, Integrative Organismal Biology, Volume 5, Issue 1, 2023, obad039, 
https://doi.org/10.1093/iob/obad039

ABSTRACT: Species ecology and life history patterns are often reflected in 
animal morphology. Blue whales are globally distributed, with distinct 
populations that feed in different productive coastal regions worldwide. Thus, 
they provide an opportunity to investigate how regional ecosystem 
characteristics may drive morphological differences within a species. Here, we 
compare physical and biological oceanography of three different blue whale 
foraging grounds: (1) Monterey Bay, California, USA; (2) the South Taranaki 
Bight (STB), Aotearoa New Zealand; and (3) the Corcovado Gulf, Chile. 
Additionally, we compare the morphology of blue whales from these regions using 
unoccupied aircraft imagery. Monterey Bay and the Corcovado Gulf are seasonally 
productive and support the migratory life history strategy of the Eastern North 
Pacific (ENP) and Chilean blue whale populations, respectively. In contrast, 
the New Zealand blue whale population remains in the less productive STB 
year-round. All three populations were indistinguishable in total body length. 
However, New Zealand blue whales were in significantly higher body condition 
despite lower regional productivity, potentially attributable to their 
non-migratory strategy that facilitates lower risk of spatiotemporal 
misalignment with more consistently available foraging opportunities. 
Alternatively, the migratory strategy of the ENP and Chilean populations may be 
successful when their presence on the foraging grounds temporally aligns with 
abundant prey availability. We document differences in skull and fluke 
morphology between populations, which may relate to different feeding behaviors 
adapted to region-specific prey and habitat characteristics. These 
morphological features may represent a trade-off between maneuverability for 
prey capture and efficient long-distance migration. As oceanographic patterns 
shift relative to long-term means under climate change, these blue whale 
populations may show different vulnerabilities due to differences in migratory 
phenology and feeding behavior between regions.

The full article is open access, and available online: 
https://academic.oup.com/iob/advance-article/doi/10.1093/iob/obad039/7438866?login=true

Please do not hesitate to reach out with any questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow, PhD (she/her)
Postdoctoral Scholar
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New Publication: Blue whale foraging and reproductive effort are related to environmental conditions

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am excited to share our recent publication in 
Ecology and Evolution:

Barlow, D. R., Klinck, H., Ponirakis, D., Branch, T. A., & Torres, L. G. 
(2023). Environmental conditions and marine heatwaves influence blue whale 
foraging and reproductive effort. Ecology and Evolution, 13, e9770. 
https://doi.org/10.1002/ece3.9770

Abstract: Animal behavior is motivated by the fundamental need to feed and 
reproduce, and these behaviors can be inferred from spatiotemporal variations 
in biological signals such as vocalizations. Yet, linking foraging and 
reproductive effort to environmental drivers can be challenging for 
wide-ranging predator species. Blue whales are acoustically active marine 
predators that produce two distinct vocalizations: song and D calls. We 
examined environmental correlates of these vocalizations using continuous 
recordings from five hydrophones in the South Taranaki Bight region of Aotearoa 
New Zealand to investigate call behavior relative to ocean conditions and infer 
life history patterns. D calls were strongly correlated with oceanographic 
drivers of upwelling in spring and summer, indicating associations with 
foraging effort. In contrast, song displayed a highly seasonal pattern with 
peak intensity in fall, which aligned with the timing of conception inferred 
from whaling records. Finally, during a marine heatwave, reduced foraging 
(inferred from D calls) was followed by lower reproductive effort (inferred 
from song intensity).

The full article is open access, and available online: 
https://onlinelibrary.wiley.com/doi/10.1002/ece3.9770

Please do not hesitate to contact me with any questions or to request a PDF 
copy.

Cheers,
Dawn

Dawn Barlow, PhD (she/her)
Postdoctoral Scholar
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Temporal occurrence of three blue whale populations in New Zealand waters from passive acoustic monitoring

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to share our recent publication in the 
Journal of Mammalogy:

Barlow, D.R., Klinck, H., Ponirakis, D., Holt Colberg, M., Torres, L.G. (2022). 
Temporal occurrence of three blue whale populations in New Zealand waters from 
passive acoustic monitoring, Journal of Mammalogy. 
https://doi.org/10.1093/jmammal/gyac106

Abstract: Describing spatial and temporal occurrence patterns of wild animal 
populations is important for understanding their evolutionary trajectories, 
population connectivity, and ecological niche specialization, with relevance 
for effective management. Throughout the world, blue whales produce stereotyped 
songs that enable identification of separate acoustic populations. We harnessed 
continuous acoustic recordings from five hydrophones deployed in the South 
Taranaki Bight (STB) region of Aotearoa New Zealand from January 2016 to 
February 2018. We examined hourly presence of songs from three different blue 
whale populations to investigate their contrasting ecological use of New 
Zealand waters. The New Zealand song was detected year-round with a seasonal 
cycle in intensity (peak February-July), demonstrating the importance of the 
region to the New Zealand population as both a foraging ground and potential 
breeding area. The Antarctic song was present in two distinct peaks each year 
(June-July; September-October) and predominantly at the offshore recording 
locations, suggesting northbound and southbound migration between feeding and 
wintering grounds. The Australian song was only detected during a 10-day period 
in January 2017, implying a rare vagrant occurrence. We therefore infer that 
the STB region is the primary niche of the New Zealand population, a migratory 
corridor for the Antarctic population, and outside the typical range of the 
Australian population.

The full article is available online: 
https://academic.oup.com/jmammal/advance-article/doi/10.1093/jmammal/gyac106/6873135?searchresult=1
Please do not hesitate to contact me with any questions or to request a PDF 
copy.

Cheers,
Dawn

Dawn Barlow, PhD (she/her)
Postdoctoral Scholar
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: blue whales and earthquakes

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to share our recent publication in 
Royal Society Open Science:

Barlow DR, Estrada Jorge M, Klinck H, Torres LG. 2022. Shaken, not stirred: 
blue whales show no acoustic response to earthquake events. Royal Society Open 
Science. 9:220242. https://doi.org/10.1098/rsos.220242

Abstract: Quantifying how animals respond to disturbance events bears relevance 
for understanding consequences to population health. We investigate whether 
blue whales respond acoustically to naturally occurring episodic noise by 
examining calling before and after earthquakes (27 040 calls, 32 earthquakes; 
27 January-29 June 2016). Two vocalization types were evaluated: New Zealand 
blue whale song and downswept vocalizations ('D calls'). Blue whales did not 
alter the number of D calls, D call received level or song intensity following 
earthquakes (paired t-tests, p > 0.7 for all). Linear models accounting for 
earthquake strength and proximity revealed significant relationships between 
change in calling activity surrounding earthquakes and prior calling activity 
(D calls: R2 = 0.277, p < 0.0001; song: R2 = 0.080, p = 0.028); however, these 
same relationships were true for 'null' periods without earthquakes (D calls: 
R2 = 0.262, p < 0.0001; song: R2 = 0.149, p = 0.0002), indicating that the 
pattern is driven by blue whale calling context regardless of earthquake 
presence. Our findings that blue whales do not respond to episodic natural 
noise provide context for interpreting documented acoustic responses to 
anthropogenic noise sources, including shipping traffic and petroleum 
development, indicating that they potentially evolved tolerance for natural 
noise sources but not novel noise from anthropogenic origins.

The full article is open access, and available online: 
https://royalsocietypublishing.org/doi/10.1098/rsos.220242

Cheers,
Dawn

Dawn Barlow, PhD (she/her)
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Forecasting blue whale distribution, with applications for spatial management

[Barlow, Dawn Renee]

Dear MARMAM Community,

I am pleased to share our recent publication in the Journal of Applied Ecology:

Barlow, D. R., & Torres, L. G. (2021). Planning ahead: Dynamic models forecast 
blue whale distribution with applications for spatial management. Journal of 
Applied Ecology, 00, 1-12. https://doi.org/10./1365-2664.13992

ABSTRACT:

  1.  Resources in the ocean are ephemeral, and effective management must 
therefore account for the dynamic spatial and temporal patterns of ecosystems 
and species of concern. We focus on the South Taranaki Bight (STB) of New 
Zealand, where upwelling generates productivity and prey to support an 
important foraging ground for blue whales that overlaps with anthropogenic 
pressure from industrial activities.
  2.  We incorporate regional ecological knowledge of upwelling dynamics, 
physical-biological coupling, and associated lags in models to forecast sea 
surface temperature (SST) and net primary productivity (NPP) with up to three 
weeks lead time. Forecasted environmental layers are then implemented in 
species distribution models to predict suitable blue whale habitat in the STB. 
Models were calibrated using data from the austral summers of 2009-2019, and 
ecological forecast skill was evaluated by predicting to withheld data.
  3.  Boosted regression tree models skillfully forecasted SST (CV deviance 
explained=0.969-0.970) and NPP (CV deviance explained=0.738-0.824). The 
subsequent blue whale distribution forecast models had high predictive 
performance (AUC=0.889), effectively forecasting suitable habitat on a daily 
scale with 1-3 weeks lead time.
  4.  The spatial location and extent of forecasted blue whale habitat was 
variable, with the proportion of petroleum and mineral permit areas that 
overlapped with daily suitable habitat ranging from 0-70%. Hence, the STB and 
these forecast models are well-suited for dynamic management that could reduce 
anthropogenic threats to whales while decreasing regulatory burdens to industry 
users relative to a traditional static protected area.
  5.  Synthesis and applications: We develop and test ecological forecast 
models that predict sea surface temperature, net primary productivity, and blue 
whale suitable habitat up to three weeks in the future within New Zealand's 
South Taranaki Bight region. These forecasts of whale distribution can be 
effectively applied for dynamic spatial management due to model foundation on 
quantified links and lags between physical forcing and biological responses. A 
framework to operationalize these forecasts through a user-driven application 
is in development to proactively inform conservation management decisions. This 
framework is implemented through stakeholder engagement, allows flexibility 
based on management objectives, and is amenable to improvement as new knowledge 
and feedback are received.

The full article is open access, and available online: 
https://besjournals.onlinelibrary.wiley.com/doi/10./1365-2664.13992

Please feel free to contact me 
(dawn.bar...@oregonstate.edu) with any 
questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow (she/her)
PhD Candidate
Marine Mammal Institute | Department of Fisheries, Wildlife, and Conservation 
Sciences
Oregon State University | Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Temporal and spatial lags between wind, coastal upwelling, and blue whale occurrence

[Barlow, Dawn Renee]

Dear MARMAM Community,

On behalf of my coauthors, I am excited to share our recent publication in 
Scientific Reports:

Barlow, D.R., Klinck, H., Ponirakis, D. Garvey, C., Torres, L. G. Temporal and 
spatial lags between wind, coastal upwelling, and blue whale occurrence. Sci 
Rep 11, 6915 (2021). https://doi.org/10.1038/s41598-021-86403-y

ABSTRACT: Understanding relationships between physical drivers and biological 
response is central to advancing ecological knowledge. Wind is the physical 
forcing mechanism in coastal upwelling systems, however lags between wind input 
and biological responses are seldom quantified for marine predators. Lags were 
examined between wind at an upwelling source, decreased temperatures along the 
upwelling plume's trajectory, and blue whale occurrence in New Zealand's South 
Taranaki Bight region (STB). Wind speed and sea surface temperature (SST) were 
extracted for austral spring-summer months between 2009-2019. A hydrophone 
recorded blue whale vocalizations October 2016-March 2017. Timeseries 
cross-correlation analyses were conducted between wind speed, SST at different 
locations along the upwelling plume, and blue whale downswept vocalizations (D 
calls). Results document increasing lag times (0-2 weeks) between wind speed 
and SST consistent with the spatial progression of upwelling, culminating with 
increased D call density at the distal end of the plume three weeks after 
increased wind speeds at the upwelling source. Lag between wind events and blue 
whale aggregations (n = 34 aggregations 2013-2019) was 2.09 ± 0.43 weeks. 
Variation in lag was significantly related to the amount of wind over the 
preceding 30 days, which likely influences stratification. This study enhances 
knowledge of physical-biological coupling in upwelling ecosystems and enables 
improved forecasting of species distribution patterns for dynamic management.

The full article is open access, and available online: 
https://www.nature.com/articles/s41598-021-86403-y

Please feel free to contact me 
(dawn.bar...@oregonstate.edu) with any 
questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow
PhD Candidate
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Blue whale habitat modeling under different oceanographic regimes

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to announce our recent publication in 
Marine Ecology Progress Series:

Barlow DR, Bernard KS, Escobar-Flores P, Palacios DM, Torres LG (2020) Links in 
the trophic chain: modeling functional relationships between in situ 
oceanography, krill, and blue whale distribution under different oceanographic 
regimes. Mar Ecol Prog Ser 642:207-225.

ABSTRACT: The response of marine predators to global climate change and 
shifting ocean conditions is tightly linked with their environment and prey. 
Environmental data are frequently used as proxies for prey availability in 
marine predator distribution models, as the ephemeral nature of prey makes 
sampling difficult. For this reason, the functional, ecological links between 
environment, prey, and predator are rarely described or explicitly tested. We 
used 3 years of vessel-based whale survey data paired with oceanographic 
sampling and hydroacoustic backscatter to model trophic relationships between 
water column structure, krill availability, and blue whale Balaenoptera 
musculus brevicauda distribution in New Zealand's South Taranaki Bight region 
under typical (2014 and 2017) and warm (2016) austral summer oceanographic 
regimes. The warm regime was characterized by a shallower mixed layer, and a 
stronger, thicker, and warmer thermocline. Boosted regression tree models 
showed that krill metrics predicted blue whale distribution (typical regime = 
36% versus warm regime = 64% cross-validated deviance explained) better than 
oceanography (typical regime = 19% versus warm regime = 31% cross-validated 
deviance explained). However, oceanographic features that predicted more krill 
aggregations (typical regime) and higher krill density (warm regime) aligned 
closely with the features that predicted higher probability of blue whale 
presence in each regime. Therefore, this study confirms that environmental 
drivers of prey availability can serve as suitable proxies for blue whale 
distribution. Considering changing ocean conditions that may influence the 
distribution of marine predators, these findings emphasize the need for models 
based on functional relationships, and calibrated across a broad range of 
conditions, to inform effective conservation management.

The full article is open access, and available online: 
https://doi.org/10.3354/meps13339

Please feel free to contact me 
(dawn.bar...@oregonstate.edu) with any 
questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow
PhD Student
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Insight into the kinematics of blue whale surface foraging through drone observations and prey data

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to announce our recent publication in 
PeerJ:

Torres LG, Barlow DR, Chandler TE, Burnett JD. 2020. Insight into the 
kinematics of blue whale surface foraging through drone observations and prey 
data. PeerJ 8:e8906 http://doi.org/10.7717/peerj.8906

ABSTRACT: To understand how predators optimize foraging strategies, extensive 
knowledge of predator behavior and prey distribution is needed. Blue whales 
employ an energetically demanding lunge feeding method that requires the whales 
to selectively feed where energetic gain exceeds energetic loss, while also 
balancing oxygen consumption, breath holding capacity, and surface recuperation 
time. Hence, blue whale foraging behavior is primarily driven by krill patch 
density and depth, but many studies have not fully considered surface feeding 
as a significant foraging strategy in energetic models. We collected predator 
and prey data on a blue whale (Balaenoptera musculus brevicauda) foraging 
ground in New Zealand in February 2017 to assess the distributional and 
behavioral response of blue whales to the distribution and density of krill 
prey aggregations. Krill density across the study region was greater toward the 
surface (upper 20 m), and blue whales were encountered where prey was 
relatively shallow and more dense. This relationship was particularly evident 
where foraging and surface lunge feeding were observed. Furthermore, New 
Zealand blue whales also had relatively short dive times (2.83 ± 0.27 SE min) 
as compared to other blue whale populations, which became even shorter at 
foraging sightings and where surface lunge feeding was observed. Using an 
unmanned aerial system (UAS; drone) we also captured unique video of a New 
Zealand blue whale's surface feeding behavior on well-illuminated krill 
patches. Video analysis illustrates the whale's potential use of vision to 
target prey, make foraging decisions, and orient body mechanics relative to 
prey patch characteristics. Kinematic analysis of a surface lunge feeding event 
revealed biomechanical coordination through speed, acceleration, head 
inclination, roll, and distance from krill patch to maximize prey engulfment. 
We compared these lunge kinematics to data previously reported from tagged blue 
whale lunges at depth to demonstrate strong similarities, and provide rare 
measurements of gape size, and krill response distance and time. These findings 
elucidate the predator-prey relationship between blue whales and krill, and 
provide support for the hypothesis that surface feeding by New Zealand blue 
whales is an important component to their foraging ecology used to optimize 
their energetic efficiency. Understanding how blue whales make foraging 
decisions presents logistical challenges, which may cause incomplete sampling 
and biased ecological knowledge if portions of their foraging behavior are 
undocumented. We conclude that surface foraging could be an important strategy 
for blue whales, and integration of UAS with tag-based studies may expand our 
understanding of their foraging ecology by examining surface feeding events in 
conjunction with behaviors at depth.

The full article is open access, and available online: 
https://peerj.com/articles/8906/

Please feel free to contact 
leigh.tor...@oregonstate.edu with any 
questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow
PhD Student
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu

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[MARMAM] New publication: Assessment of blue whale skin condition

[Barlow, Dawn Renee]

Dear MARMAM community,

On behalf of my coauthors, I am pleased to announce our recent publication in 
Frontiers in Marine Science:

Barlow, D. R., Pepper, A. L., & Torres, L. G. (2019). Skin deep: An assessment 
of New Zealand blue whale skin condition. Frontiers in Marine Science, 6, 757.

ABSTRACT: Skin condition assessment of wildlife can provide insight into 
individual and population health. Yet, logistics can limit skin condition 
assessment of large whales. We developed a standardized, quantitative protocol 
using photographs to assess skin condition of blue whales in New Zealand, and 
demonstrate the value gained by testing hypotheses, documenting new 
morphologies, and establishing baselines that can be monitored for change. We 
reviewed a photo-identification catalog to compile common markings, categorized 
markings according to existing definitions, and described markings not 
previously documented. Photographs of blue whale skin (n=1,466) were assessed 
to quantify marking prevalence, severity, and co-occurrence patterns. Of the 
whales assessed (n=148), 96.6% had cookie cutter shark bites, 80.4% had blister 
lesions, 56.0% had pigmentation blazes on the dorsal fin, and 33.7% had holes 
in the dorsal fin. Additionally, 35.8% had “starburst” lesions, a previously 
undocumented marking. Blister and cookie cutter shark bite severity did not 
accumulate linearly, indicating that the two marking types are unrelated. There 
was a positive relationship between blister severity and number of starbursts, 
indicating that the two could be related; based on morphological similarities, 
starburst lesions may derive from ruptured blisters. Whales with holes in their 
dorsal fin had significantly higher blister severity than those without, 
indicating that these markings could be related; this is supported by observed 
blisters on dorsal fins of blue whales. There was a significantly higher 
probability of fresher cookie cutter shark bites on whales observed at more 
northerly latitudes, but no relationship between blister severity or number of 
starbursts and latitude. These latitudinal patterns indicate that blue whales 
in New Zealand accumulate cookie cutter shark bites at more northerly 
latitudes; this finding is supported by the known range of cookie cutter sharks 
in New Zealand waters. Of the eight individual whales re-sighted across 
multiple years, there was no uniform pattern in lesion change over time, 
however individual cases revealed lesion healing over a multi-year timeframe. 
Our protocol for quantifying skin condition can be applied to any cetacean 
photo-identification catalog, and can be used to compare across individuals and 
populations, and explore causal links between skin condition and cetacean 
health.

The full article is open access, and available online: 
https://www.frontiersin.org/articles/10.3389/fmars.2019.00757/full?_source=Email_to_authors__medium=Email_content=T1_11.5e1_author_campaign=Email_publication==Frontiers_in_Marine_Science=488863

Please feel free to contact me at dawn.bar...@oregonstate.edu with any 
questions or to request a PDF copy.

Cheers,
Dawn

Dawn Barlow
PhD Student
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu
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[MARMAM] New publication: Estimating morphometric attributes of baleen whales from small UASs

[Barlow, Dawn Renee]

Dear colleagues,

We are pleased to announce the publication of our paper in Marine Mammal 
Science:

Burnett, J. D., Lemos, L., Barlow, D. R., Wing, M. G., Chandler, T. E., Torres, 
L. G. (2018). Estimating morphometric attributes of baleen whales with 
photogrammetry from small UAS: a case study with blue and gray whales. Marine 
Mammal Science. doi:10./mms.12527

ABSTRACT: Small unmanned aircraft systems (sUASs) are fostering novel 
approaches to marine mammal research, including baleen whale photogrammetry, by 
providing new observational perspectives. We collected vertical images of 89 
gray and 6 blue whales using low cost sUASs to examine the accuracy of image 
based morphometry. Moreover, measurements from 192 images of a 1 m calibration 
object were used to examine four different scaling correction models. Results 
indicate that a linear mixed model including an error term for flight and date 
contained 0.17 m less error and 0.25 m less bias than no correction. We used 
the propagation uncertainty law to examine error contributions from scaling and 
image measurement (digitization) to determine that digitization accounted for 
97% of total variance. Additionally, we present a new whale body size metric 
termed Body Area Index (BAI). BAI is scale invariant and is independent of body 
length (R2 = 0.11), enabling comparisons of body size within and among 
populations, and over time. With this study we present a three program analysis 
suite that measures baleen whales and compensates for lens distortion and 
corrects scaling error to produce 11 morphometric attributes from sUAS imagery. 
The program is freely available and is expected to improve processing 
efficiency and analytical continuity.

The full article is open access, and is available online: 
https://onlinelibrary.wiley.com/doi/full/10./mms.12527

Furthermore, the code for the analysis programs are freely available, and can 
be accessed via the supplemental materials.

Cheers,
Dawn

Dawn Barlow
PhD Student
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu
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[MARMAM] New publication: Documentation of a New Zealand blue whale population

[Barlow, Dawn Renee]

Dear colleagues,

On behalf of my coauthors, I am pleased to announce the publication of our 
paper in Endangered Species Research:

Barlow DR, Torres LG, Hodge KB, Steel D, Baker CS, Chandler TE, Bott N, 
Constantine R, Double MC, Gill P, Glasgow D, Hamner RM, Lilley C, Ogle M, Olson 
PA, Peters C, Stockin KA, Tessaglia-hymes CT, Klinck H (2018) Documentation of 
a New Zealand blue whale population based on multiple lines of evidence. 
Endanger Species Res 36:27–40

ABSTRACT: Species conservation depends on robust population assessment. Data on 
population abundance, distribution, and connectivity are critical for effective 
management, especially as baseline information for newly documented 
populations. We describe a pygmy blue whale Balaenoptera musculus brevicauda 
population in New Zealand waters with year-round presence that overlaps with 
industrial activities. This population was investigated using a 
multidisciplinary approach, including analysis of survey data, sighting 
records, acoustic data, identification photographs, and genetic samples. Blue 
whales were reported during every month of the year in the New Zealand 
Exclusive Economic Zone, with reports concentrated in the South Taranaki Bight 
(STB) region, where foraging behavior was frequently observed. Five hydrophones 
in the STB recorded the New Zealand blue whale call type on 99.7% of recording 
days (January to December 2016). A total of 151 individuals were 
photo-identified between 2004 and 2017. Nine individuals were resighted across 
multiple years. No matches were made to individuals identified in Australian or 
Antarctic waters. Mitochondrial DNA haplotype frequencies differed 
significantly between New Zealand (n = 53 individuals) and all other Southern 
Hemisphere blue whale populations, and haplotype diversity was significantly 
lower than all other populations. These results suggest a high degree of 
isolation of this New Zealand population. Using a closed capture-recapture 
population model, our conservative abundance estimate of blue whales in New 
Zealand is 718 (SD = 433, 95% CI = 279-1926). Our results fill critical 
knowledge gaps to improve management of blue whale populations in New Zealand 
and surrounding regions.

The full article is open access, and is available online: 
http://www.int-res.com/abstracts/esr/v36/p27-40/

Cheers,
Dawn

Dawn Barlow
MSc Student and Graduate Research Assistant
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu
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[MARMAM] ABSTRACT DEADLINE EXTENDED - NWSSMM 2018 annual meeting

[Barlow, Dawn Renee]

Dear all,

We have extended the abstract submission deadline, and will now be accepting 
abstracts through Friday, April 20th!

The annual meeting of the Northwest Student Chapter of the Society for Marine 
Mammalogy (NWSSMM) will take place May 12-13, 2018. The chapter encompasses 
students who are based in Alaska, British Columbia, Washington, Oregon, and 
northern California, or who conduct research in these locations. We are excited 
to announce that this year's conference will be held at Oregon State 
University's Hatfield Marine Science Center in Newport, Oregon!

Saturday, May 12th will be filled with student oral and poster presentations, a 
philosopher's cafe where students can engage in discussions with established 
researchers in the field, and a group dinner. Sunday, May 13th we will have the 
option for students to participate in a necropsy (space limited) or take a tour 
of the Oregon Coast Aquarium (additional fee may apply).

Registration is now open! The cost for attendance is TBA (max $20), and will be 
due at the beginning of the conference. Please register using the following 
link: http://bit.ly/2nwpOGq

Abstract submissions will be accepted through Friday, April 20th. Guests 
(students or non-students) who are are not interested in presenting but would 
like to attend are still encouraged to register and join us for the conference! 
Registration will be accepted at any time, including the day of the meeting. 
However, please keep in mind that early registration is appreciated so that we 
can ensure everything runs as smoothly as possible.

We look forward to seeing you on the Oregon coast in May!

Dawn Barlow and Michelle Fournet
NWSSMM 2018 conference organizers
Facebook event: https://www.facebook.com/events/180826859347101/

Dawn Barlow
MSc Student and Graduate Research Assistant
Department of Fisheries and Wildlife, Marine Mammal Institute
Oregon State University, Hatfield Marine Science Center
Geospatial Ecology of Marine Megafauna Lab
dawn.bar...@oregonstate.edu
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