1. Janice Talley1, Nashelly Meneses1, Randy Harper, and Marilyn Swift, Russell Benford1
1Department of Biological Sciences, Northern Arizona University, Field Experience in Conservation Biology
!!
!INTRODUCTION!
!ACKNOWLEDGMENTS
DISCUSSIONABSTRACT!
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!RESULTS
!REFERENCES
!METHODS! CONCLUSIONS
! Wedge-tailed Shearwaters (Puffinus pacificus) are
migratory seabirds that are widespread across the Indian and
Pacific Oceans. This species of conservation concern often only
breeds on small islands. In the Northern Mariana Islands,
Shearwaters nest on Mañagaha, a small island off the coast of
Saipan. This population of Shearwaters occasionally experiences
outbreaks of ringworm. This fungal infection, caused by
dermatophytes that break down keratin, is common and easy to
treat. Untreated infections can have detrimental effects on the
bird’s health. Detection and treatment of outbreaks depend on
the identification of factors that promote infection. These factors
could include: microenvironment (soil moisture, temperature,
pH), spatial arrangement of the burrows (distribution and
orientation ), and proximity to the septic tank. These factors were
measured in burrows (n=103) that were active in the previous
breeding season and in which the burrow condition (infected or
not infected) was known. Probability of infection in response to
these factors was determined using a logistic regression. Our
results show that soil moisture (X2=3.87 p=0.049), temperature
(X2=8.57 p=0.0034), and distance from septic tank (X2=10.83
p=0.001) affect the probability of ringworm infection.
Understanding factors that contribute to infection probability will
result in more effective control of the ringworm infection and
improved breeding success of Mañagaha’s Shearwater
population. Be consistent on how you list distribution and
orientation. !
!
Factors Affecting Probability of Ringworm Infection
in Wedge-tailed Shearwaters (Puffinus pacificus)
! Wedge-tailed Shearwaters (Puffinus pacificus) are a
widely-distributed tropical seabird with breeding sites ranging
from Madagascar in the western Indian Ocean to the
Revillagigedo Islands in the Eastern Pacific [1]. Characteristically,
these birds only nest on small islands. In the Northern Mariana
Islands, Shearwaters nest on Mañagaha, a small coral cay within
the Saipan Lagoon. This population of Shearwaters occasionally
experiences outbreaks in ringworm. These outbreaks tend to
affect only certain burrows, which suggests that environmental
factors might influence ringworm infection. This infection, caused
by fungal dermatophytes from three genera (Epidermophyton,
Microsporum, Trichophyton), is common and easy to treat.
However, information on environmental factors that contribute to
the onset of this infection is lacking.!
What factors could affect the probability of infection?!
• Microenvironment (soil pH, moisture, temperature)!
• Spatial Arrangement of the burrows (distribution and
orientation)!
• Distance from keratinous material (from septic tank)!
All of the burrows that were active in the
previous breeding season (n=103) were
used in order to compare environmental
parameters to burrow condition (infected or
not infected). !
• Microenvironment:!
• Recorded soil moisture and
temperature biweekly using a
Rapitest 1835 –Way Soil Analyzer!
• Prepared soil suspension (1:1 soil
water) from each burrow and
measured pH with a pH meter [2]!
• Spatial Arrangement:!
• Determined orientation with a
compass; broken into eight general
aspects (North, Northeast, South, etc)!
• Global position was recorded for each
burrow and the septic tank!
• Coordinates were used to determine
their distribution (Clustered, Random,
Dispersed) of all and of infected
burrows with the Average Nearest
Neighbor tool in ArcMap [7] !
• Distance between septic tank and
individual burrows was determined
with Point Distance tool in ArcMap [7]!
The probability of infection increases as moisture levels
increase, temperature levels decrease, and distance from septic
tank decreases.!
!Although studies have looked at the effects of the factors addressed
in this study on other fungal pathogens [3,4,5], little has been reported on
how these factors affect fungal species that cause ringworm or the
environmental conditions as they relate to the host. Similar to studies that
looked at moisture and temperature, there appears to be a range where
this pathogen is effectively causing infection [5]. Although pH has shown to
affect other soil loving, geophilic, fungal species [4], there are currently no
data to support that pH affects the probability of ringworm infection on
Shearwaters. Nor is there any evidence of orientation affecting infection
probability, even though orientation can affect fungal load in other bird
species [3].!
!Burrows followed the arrangement of limited available habitat (i,e.,
clustered). However, the evenly dispersed pattern of infection within these
clusters is unexpected. This could be explained by the low sample size. To
more rigorously evaluate this relationship, a study across multiple years
should be conducted. !
!Our results indicate that proximity to the septic tank increases the
probability of infection. A study [6] reports that sludge fields around septic
tanks contain a high level of keratinous material. Geophilic dematophytes
use this host material to sustain themselves until a more suitable host,
such as a Wedge-tailed Shearwater, is available. !
! With this information, the burrows that are at a higher risk of
infection, burrows with consistently lower temperatures, higher moisture,
and closer to the septic tank, can be identified. !
!
Future Plans:!
• Develop a predictive map of hot spots for infection on Mañagaha!
• Identify specific dermatophyte strain causing this ringworm infection!
Figure
1:
Probability
of
infec/on
increases
as
moisture
levels
increase
n=103
X2=3.87
p=0.049
Figure
2:
As
Temperature
increases,
probability
of
infec/on
decreases
n=103
X2=8.57
p=0.0034
Figure
3:
As
distance
from
the
sep/c
tank
increases,
probability
of
infec/on
decreases
n=102
X2=10.83
p=0.001
[7]
Figure 4: In general, Shearwater burrows were clustered,
whereas infected burrows were evenly dispersed!
Z-score: 2.55 p=0.01 [7]!
Supported Hypotheses: !
!1. Soil Moisture !
!2. Soil Temperature !
!3. Distance to the septic tank !
No evidence to support: !
!1. Soil pH!
!2. Burrow orientation!
!3. Burrow distribution !
[1] Whittow, G. Causey. 1997. Wedge-tailed Shearwater (Puffinus pacificus), The Birds of North America Online
(A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; !
[2]Keyvan Pakshir, Moosa Rahimi Ghiasi, Kamiar Zomorodian, and Ali Reza Gharavi, “Isolation and Molecular
Identification of Keratinophilic Fungi from Public Parks Soil in Shiraz, Iran,” BioMed Research International, vol.
2013, Article ID 619576, 5 pages, 2013. doi:10.1155/2013/619576!
[3] Goodenough, A. E., & Stallwood, B. (2012). Differences in culturable microbial communities in bird nestboxes
according to orientations and influences on offspring quality in great tits (parus major). Microb Ecol, 63, 986-995.!
[4] Kolli, S. C., Nagamani, A., & Ratnakumari, R. (2012). Growth response of trichoderma islates against varying
ph levels. International Journal of Environmental Biology, 2(4), 180-182.!
[5] Kim, Y. K., Xiao, C. L., & Rogers, J. D. (2005). Influence of culture media and environmental factors on
mycelial growth and pyenidial production of sphaeropsis pyriputrescens. Mycologia, 97(1), 25-32.!
[6] Maruthi, Y. A., Hossain, K., Priya, D. H., & Tejaswi, B. (2012). Prevalence of keratinophilic fungi from sewage
sludge at some wastewater out lets along the coast of Visakhapatnam: A case study. Advances in Applied
Science Research, 3(1), 605-610. !
[7] ESRI (Environmental Systems Resource Institute). 2014. ArcMap 10.1. ESRI, Redlands, California. !
!
Melissa Janezic, Hervin Jacinto, Hannah Lamb, Victoria Ptak, Lisa Bertin, FECB collegues,
FECB Student Conservation Research Grant, ASNAU & USAC Block Grants (GO scholarship),
Northern Marianas College, Tasi Tours
There was no significant relationship between soil pH and
infection (n=97 X2=2.39 p=0.12), nor between burrow
orientation and infection (n=101 X2=8.34 p=0.40)
!
0
1
24.5
25
25.5
26
26.5
27
27.5
28
28.5
Probability
of
infection
Temperature
C
0
1
0
1
2
3
4
5
6
Probabilty
of
infection
Moisture
Levels
0
1
0
20
40
60
80
100
120
140
160
180
200
Probabilty
of
infection
Distance
from
septic
tank
(m)