Tuesday, February 15, 2022

Alex & Alarie presented their work on gray squirrel dreys this week at the Midwest Fish & Wildlife Conference in Des Moines. It was the first professional meeting for them and the Bennies did a great job!
 

 

Wednesday, July 7, 2021

Alarie (left) and Alex (right)
SUMMER RESEARCH 2021


This summer I've teamed up with a colleague up at the Natural Resources Research Institute in Duluth MN to conduct some non fish-related work (gasp!).  Michael Joyce, PhD and I attended the same grad program and always talked about conducting some work together. This summer he needed access to a few thousand acres for his grad student Taylor, and we hatched a plan to conduct some research of our own in the SJU arboretum.







Alarie uses a laser tool to measure drey height (right) Tree ID (left)




After interviewing many students, we selected Alexandria Armbrister and Alarie Chu for summer research students. The Bennies are investigating the thermal properties of grey squirrel (Sciurus carolinensis) nests (dreys). Their work includes collection of temperature fluctuation data within the dreys via temperature loggers, drey-site selection data, assessment of the physical area surrounding dreys, and finally drey material analysis.


The main knowledge gaps for modeling squirrel rest site temperature and energetics are, 1) quantifying variation in drey size and biomass of nesting materials, and 2) gathering empirical data to develop/test a model.
Michael Joyce and myself in the field

Ultimately, this information will be integrated with an energetics model for the grey squirrel to evaluate interactions between resting behavior, ambient temperature, and daily energy expenditure.
 

Friday, March 12, 2021

Due to COVID, it was necessary for summer research for 2020 to be conducted virtually. In a deviation from the typical fish-oriented physiology and behavior work, Tyler Ehrke  (summer research student), collaborators at CSB/SJU and I, decided to make the most of the situation and study the effect of the pandemic on student health.
The start of 2020 was highlighted with the outbreak of a new coronavirus (SARS-CoV-2) and the associated disease (COVID-19) which quickly escalated to a global pandemic. Quarantines were established early on and many universities were forced to move to distanced learning, an online learning format. The associated fear of an uncertain future and new learning format lead to anxiety amongst college-aged students. Anxiety can broadly be classified in two ways: trait anxiety and state anxiety. Trait anxiety is a stable susceptibility or a proneness to experience anxiety frequently, or a predisposed nature to anxiety.

State anxiety is defined as a transitory emotional state that varies in intensity and fluctuates over time. In other words, trait anxiety is more associated with a person’s nature, while state anxiety is more situational. For our study, we exclusively looked at state anxiety associated with the new coronavirus and pandemic. State anxiety can be broken down into two sub-categories: cognitive state anxiety and somatic state anxiety, where cognitive anxiety is how anxiety affects a person’s mind/thoughts. Somatic anxiety is then how the body responds to anxiety; responses that cannot be controlled consciously such as increased heart rate, perspiration, and altered digestive function.

To cope with anxiety, many students choose to engage in physical activity. The aim of our study therefore was to determine if student anxiety specifically related to COVID-19  could be mitigated by regular physical activity (PA). Via a large online student survey, we assessed both forms of state anxiety as well as PA within the College of St. Benedict and St John’s University (CSB/SJU) student bodies. We hypothesized that higher levels of PA will be associated with lower state anxiety in these college students.

An optional online survey was sent to both CSB/SJU student bodies. The survey was based on the State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA) measurement system formulated from the Spielberger Trait-State Anxiety Inventory. Within the survey, participants were asked questions pertaining to both divisions of state anxiety- cognitive anxiety and somatic anxiety. Participants were asked twenty-one questions pertaining to how they currently felt when taking the questionnaire versus before the pandemic.


Tyler Ehrke
As hypothesized, we found that overall, both moderate and vigorous PA were all associated with significantly reduced state anxiety for both cognitive and somatic forms. See poster for specific results or email Tehrke001@csbsju.edu 


Thursday, November 14, 2019

Summer research is complete! Paige presented her work at the Midwest Fish and Wildlife meeting early in 2020 in Springfield, Illinois.  Strong work, Paige




Tuesday, June 11, 2019

CSB/SJU Summer Research


Stumpf Lake and Lake Sagatagan
Summer 2019 kicks off summer research at St. John's University!



This year we are analyzing length at age for Northern Pike (Esox lucius) on Stumpf Lake as well as Large Mouth Bass (Micropterus salmoides) on Lake Sagatagan (Left)

Cross-section of Pike anal fin ray. This fish is aged 4 years
These campus lakes lack public launches and have lower fishing pressure than surrounding lakes.  We expect to see differences in length and age for these campus fishes when compared to similar local lakes that receive higher fishing pressure.  For aging structures, we are using a non-lethal method for Pike which uses anal fin rays.  For Largemouth Bass, fin rays do not reflect true age, so standard sagittal otolith methods are being used.

An otolith from a Largemouth Bass aged 17 years
Assisting with this research is Paige Folkerts, a Senior bio major from the College of Saint Benedict. Paige is a pre-vet student who has had an interest in fish from a young age.  She currently holds the record for the largest Pike (28") and smallest Pike (12") caught on Stumpf Lake. Paige has assisted in collection of Pike with different gear types, will be analyzing age structures on both Bass and Pike, and will create a poster to present her findings (coming soon). Additionally, Dr. Jen Schaeffer's research assistant, Amanda Bevan, is helping with Pike collection and is interested in pursuing a career in neuroscience.



Paige Folkerts and a 28" Northern Pike
Amanda Bevan determines length




Bass were collected early spring (55ยบ surface) by electroshock with the help of Joe Stewig, the Sauk Rapids Area Supervisor.  We collected 44 Large Mouth Bass. Joe was kind enough to give a demonstration on electrofishing and take students out to net the fishes. Students also assisted in recording catch numbers, length and helped remove otoliths. 


Matt Captain (summer researcher) nets a LMB
Joe Stewig collects otoliths


Jess Torrison holds a 21" LMB


Pike have been collected via Fyke netting and angling.  Currently, we have 41 Pike and would like to have 2 fish per inch designation by the end of the summer. 

Additionally, we are also looking at how the gear type used for collection affects lactate levels in Bluegill (Lepomis macrochirus). This study is ongoing. 

Updates soon!


Saturday, January 13, 2018

Light in lakes and forage habitat

Figure 1.  Capture probabilities for Siscowet Lake Trout at different light intensities
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Recently, we have been investigating how fish habitat changes with daily and seasonal light changes.  With the help of Bryan Matthias, a post-doc at UMD, we have created a light model for Lake Superior that predicts changes in Siscowet Lake Trout foraging habitat on an hourly, daily and seasonal time scale.




Figure 2. A photon of light's path through water



Using Siscowet prey capture data from Keyler et al. (2015), we are able to determine the light intensity associated with 50% prey capture during foraging trials (Fig. 1).  We can then calculate the depth within Superior associated with this light intensity throughout the day and seasons using the model.  






Figure 3.  Changes in solar altitude and angle with seasons

Our model accounts for reflection at the lake's surface, refraction by water, and attenuation within the water (Fig. 2).  Due to the angle and altitude of the sun associated with different seasons (Fig. 3), light penetrates deeper in the summer compared to the winter season. Siscowet forage habitat is therefore greater in the summer, than in the winter (Fig. 4).  




Additionally, we are working on calculating the daily light changes within Lake Superior as well as how light penetration, and respective siscowet forage habitat, will change with climate warming. 

Figure 4.  Solar maximum siscowet habitat depths for cross-section of Lake Superior (right) and associated geographical distribution (left) for spring, summer, fall and winter (from top) within the Western Arm of Lake Superior. 

Publication Link: https://link.springer.com/article/10.1007/s10750-019-3888-9