DOI: 10.5061/dryad.g1jwstr24
title: Variation in pathogen load and the pathogen load–infectiousness relationship broaden avian malaria’s distribution

description: The infectiousness of host species and the feeding patterns of vectors
 influence pathogen distribution and transmission intensity. Two aspects of
 host infectiousness shape transmission but are underappreciated: the
 relationship between pathogen load and infectiousness and variability in
 pathogen load within species. We quantified the relationship between host
 parasitemia for avian malaria (Plasmodium relictum) and infectiousness for
 biting Culex quinquefasciatus mosquitoes using experimentally infected
 birds. We used this relationship and 4,218 samples from wild birds to
 estimate the relative importance of hosts’ acute and chronic stages of
 infection, the infectiousness of 17 bird species in Hawaiʻi, and mosquito
 feeding preferences. Infectiousness to mosquitoes increased with host
 parasitemia (and temperature and time since feeding), but the
 relationship’s gradual slope led to a wide range of parasitemias being
 partly infectious to mosquitoes. Chronic stage infections create far more
 infectious mosquitoes than the acute stage, and high within-species
 variability in parasitemia led to broad overlap in the infectiousness of
 most bird species. Disproportionate feeding patterns (inferred from
 relative infection prevalence) elevated the importance of a few bird
 species in transmission, but broad overlap in species infectiousness
 resulted in most host communities having similar total infectiousness.
 Similar community infectiousness helped explain the widespread
 distribution of avian malaria throughout Hawaiʻi despite highly variable
 species communities - it was detected at 63/64 moderately well-sampled
 sites. These results demonstrate the importance of the shape of the
 pathogen load-infectiousness relationship and within-species variability
 in pathogen load in influencing a pathogen’s host range, transmission
 intensity, and spatial distribution.
description: This dataset contains the data and code required to replicate
 analyses in Seidl et al. 2025, which examines the contribution of host
 community composition to pathogen transmission and distribution and how
 these are influenced by the relationship between pathogen load and
 infectiousness and variability in pathogen load within host species. The
 study system described by the data is avian malaria (<em>Plasmodium
 relictum</em>) in birds in the Hawaiian Islands, USA. Multiple files
 are included, containing data from field and laboratory studies,
 mathematical models, and published literature. Some of the files describe
 a series of experiments with mosquitoes, avian malaria, and domestic
 canaries. Other files report results from avian malaria sampling of wild
 birds in Hawaii that was conducted in 2015-2017 by the Hawai‘i Vertebrate
 Introductions and Novel Ecosystems project, in 2018-2021 by the U.S.
 Geological Survey’s Avian Malaria Genomic Research Project, and in
 2019-2020 by author C.M. Seidl as part of her Ph.D. dissertation research.
 Point count sampling data and bird density estimates generated using
 distance sampling from sites on Hawaii Island are included. Finally, files
 containing data from published experimental infection studies of native
 Hawaiian birds and <em>Culex quinquefasciatus</em> mosquitoes
 are summarized.
description: # Variation in pathogen load and the pathogen load–infectiousness
 relationship broaden avian malaria’s distribution
 [https://doi.org/10.5061/dryad.g1jwstr24](https://doi.org/10.5061/dryad.g1jwstr24) ### Description of the data and file structure - **This dataset includes R code and data files in .csv format for:** * Avian malaria experimental infections studies in birds (wild and domestic) * Mosquito infection results across different temperatures and temperature-dependent days post feeding * Avian malaria infection prevalence and demographic data for birds in Hawaii * Point count surveys and bird species density estimates by site in Hawaii #### Ethics Approval All work with wild and laboratory birds was performed under animal care and use protocols approved by the Institutional Animal Care and Use Committee at the University of California in Santa Cruz, USA (Kilpm2003). We conducted fieldwork under Hawai‘i Division of Forestry and Wildlife Protected Wildlife Permits (WL19-23; WL 17-08), USGS Bird Banding Laboratory permit numbers (#23600, #21144), and a Hawai‘i State Access and Forest Reserve Special Use Permit. #### **Acknowledgments** We thank the field teams that collected samples over the years, including the U.S. Geological Survey’s Avian Malaria Genomic Research Project team and the Hawai‘i Vertebrate Introductions and Novel Ecosystems project. We thank the State of Hawai‘i Division of Forestry and Wildlife and the Natural Area Reserve System for land access and logistical support. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Portions of the paper were developed from the [thesis of C.M. Seidl.](https://escholarship.org/uc/item/65d0n1v7) ### Files and variables #### **2020_UCSC_BF_mosquitoes_Elvis_AllPlates.csv** **Description:** Avian malaria (*Plasmodium relictum GRW4*) *infection and other data for mosquitoes (Culex quinquefasciatus*) exposed to an experimentally infected canary (*Serinus canaria domestica*) on different dates and infection levels (parasitemia) within the canary. Rows are one of three body parts tested from a mosquito. Experimental infections in birds and mosquitoes occurred in May - June 2020. Missing values have "NA" or are blank. This file is combined with **2023_BFMosquito_Aug01Dataset_age.csv** and **2023_BFMosquito_Mar01Dataset_age.csv** in analysis. ##### Column names and variables: * UNQ_ID: Unique identifier for the mosquito sample, not used. * Bird_ID: ID of the bird that was fed on using a name * Isolate: ID of GRW4 avian malaria isolate used in canary infection * Bird_DPI: Days post infection for the bird * Parasitemia: parasitemia of bird (not in percent; in fraction of cells infected) when fed on by mosquito * Bird Ct: qPCR score in CT values of canary when fed on by mosquito * Effect_BirdCT: Two digit integer version of "Bird Ct" column value * MOSQ_ID*: *ID of mosquito tested on *"Date_of*_meal" * Date_of_meal: Date of feeding (sometimes a date range) * Inc_Temp: Constant temperature in Celcius of environmental chamber that mosquito held in until dissection (18, 20, 24) * DPE: Days post exposure for mosquito * Sample_Type: Part of mosquito; we only analyzed THorax or ABdomen. SAliva data also present. * Date_of_assay: Date mosquito dissected * FAM Ct_Run1: qPCR CT score of mosquito sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * FAM Ct_Run2: qPCR CT score of mosquito sample, second run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * Ave Mosq Ct Score: Average of FAM Ct_Run1 and FAM Ct_Run2. If value = "Undetermined" for one run, this value will be same as the run for which a CT score is present. If both runs are Undetermined, this value is 0, indicating sample is negative for Plasmodium DNA. #### 2023_BFMosquito_Mar01Dataset_age.csv **Description**: Avian malaria (*Plasmodium relictum GRW4*) *infection results and other data for mosquitoes (Culex quinquefasciatus*) exposed to an experimentally infected canary (*Serinus canaria domestica*) on different dates and infection levels (parasitemia) within the canary. Rows are one of three body parts tested from a mosquito. Experimental infections in birds and mosquitoes occurred in March - May 2022. Missing values have "NA" or are blank, or contain the word "MISSING". This file is combined with **2020_UCSC_BF_mosquitoes_Elvis_AllPlates.csv** and **2023_BFMosquito_Aug01Dataset_age.csv** in analysis.  ##### Column names and variables: * UNQ_ID: Unique identifier for the mosquito sample, not used * Bird_ID: ID of the bird that was fed on using leg color band combination * Isolate: ID of GRW4 avian malaria isolate used in canary infection * Bird_DPI: Days post infection for the bird * Parasitemia: parasitemia of bird (not in percent; in fraction of cells infected) when fed on by mosquito * Bird Ct: qPCR score in CT values of canary when fed on by mosquito * Effect_BirdCT: Two digit integer version of "Bird Ct" column value * MOSQ_ID: ID of mosquito tested on *"*Date_of_meal" * MOSQ_AGE: Age in days of mosquito when it fed upon the bird * MOSQ_AGE_DIS: Age in days when the mosquito was dissected  * Date_of_meal: Date of feeding (sometimes a date range) * Inc_Temp: Constant temperature in Celcius of environmental chamber that mosquito held in until dissection (18, 20, 24, 28) * DPE: Days post exposure for mosquito * Sample_Type: Part of mosquito; we only analyzed THorax or ABdomen. SAliva data also present. * Date_of_assay: Date mosquito dissected * FAM Ct_Run1: qPCR CT score of mosquito sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * FAM Ct_Run2: qPCR CT score of mosquito sample, second run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * Ave Mosq Ct Score: Average of FAM Ct_Run1 and FAM Ct_Run2. If value = "Undetermined" for one run, this value will be same as the run for which a CT score is present. If both runs are Undetermined, this value is 0, indicating sample is negative for Plasmodium DNA. #### 2023_BFMosquito_Aug01Dataset_age.csv **Description**: Avian malaria (Plasmodium relictum GRW4) infection results and other data for mosquitoes *(Culex quinquefasciatus*) exposed to an experimentally infected canary (*Serinus canaria domestica*) on different dates and infection levels (parasitemia) within the canary. Rows are one of three body parts tested from a mosquito. Experimental infections in birds and mosquitoes occurred in April - June 2023. Missing values have "NA" or are blank. This file is combined with **2020_UCSC_BF_mosquitoes_Elvis_AllPlates.csv** and  **2023_BFMosquito_Mar01Dataset_age.csv** in analysis. ##### Column names and variables: * UNQ_ID: Unique identifier for the mosquito sample, not used. * Bird_ID: ID of the bird that was fed on using leg color band combination * Isolate: ID of GRW4 avian malaria isolate used in canary infection * Bird_DPI: Days post infection for the bird * Parasitemia: parasitemia of bird (not in percent; in fraction of cells infected) when fed on by mosquito * Bird Ct: qPCR score in CT values of canary when fed on by mosquito * Effect_BirdCT: Two digit integer version of "Bird Ct" column value * MOSQ_ID: ID of mosquito tested on *"*Date_of_meal" * MOSQ_AGE: Age in days of mosquito when it fed upon the bird * MOSQ_AGE_DIS: Age in days when the mosquito was dissected  * Date_of_meal: Date of feeding (sometimes a date range) * Inc_Temp: Constant temperature in Celcius of environmental chamber that mosquito held in until dissection (20, 26) - DPE: Days post exposure for mosquito - Sample_Type: Part of mosquito; we only analyzed THorax or ABdomen. SAliva data also present. - Date_of_assay: Date mosquito dissected * FAM Ct_Run1: qPCR CT score of mosquito sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * FAM Ct_Run2: qPCR CT score of mosquito sample, second run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * Ave Mosq Ct Score: Average of FAM Ct_Run1 and FAM Ct_Run2. If value = "Undetermined" for one run, this value will be same as the run for which a CT score is present. If both runs are Undetermined, this value is 0, indicating sample is negative for Plasmodium DNA. #### C_E_J_Birds_Combined_02222021.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection results for blood samples taken from wild-caught birds from multiple islands in Hawaii. Rows are are individual bird blood samples collected between 2014 and 2020 by authors. Empty cells indicate no value. ##### Column names and variables: * Band Number: ID for bird using United States Geological Survey metal band number. If bird was unbanded, a unique 1-9 character code assigned * SpeciesCode: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. Except "Canary" which represents domestic canary. JAWE is now WAWE. * NativevExo: Classifies bird as "Native" or "Exotic" to Hawaii * Family : Scientific family of individual * SubFamily: Scientific subfamily of individual * Genus: Scientific genus of individual * Species: Scientific species of individual * SciName: Combination of Genus and Species for individual * Sample Date: Date blood sample collected * Site Code: Abbreviated (4-letter) code for location where bird was captured and sampled * Island: Island of Hawaii where bird sampled. Values = Hawaii, Oahu, Maui, Kauai. * DNA Extraction Date: Date of DNA extraction from blood sample * Elevatio_m: Elevation in meters where birds was sampled * qPCR Date: Date of qPCR testing for extracted DNA * Infection Designation: Denotes whether sample was positive (pos) or negative (neg) for Plasmodium DNA using qPCR * Average Ct: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs.This is the average value of 2 qPCR runs. #### 2020_UCSC_HI_Birds_Slide2qPCR_All.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection measurements in wild-caught birds in Hawaii and experimentally infected canaries (*Serinus canaria domestic*) taken from blood samples. Infection measured through visual counts of parasitized cells on Giemsa-stained blood smears using microscopy and counts of Plasmodium DNA in bird blood sample measured by qPCR. Rows are individual bird blood samples. Empty cells or those with "NA" indicate no data. ##### Column names and variables: * Band Number: ID for bird using United States Geological Survey metal band number. If bird was unbanded, a unique 1-9 character code assigned * Species: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. Except "Canary" which represents domestic canary. JAWE is now WAWE. * DPI: Days post infection for the bird. If blank, this value is unknown for individual. * Sampling Date: Date blood sample collected * Status: Sample taken from wild bird (Wild) or from a bird experimentally infected in a laboratory (Lab) * Site Code: Code for location where bird was captured and sampled * Magnification: Magification of compound microscope used to examine stained blood smear * Num Parasite cells: number of parasite cells observed in blood smear * Cells Examined: number of red blood cells examined in blood smear * Parasitemia: number of parasite cells observed divided by number of red blood cells examined within blood smear * Pos_Neg: Denotes whether sample was positive (pos) or negative (neg) for Plasmodium DNA using qPCR * GRW04/11 qPCR FAM Ct_Run1: qPCR CT score of bird blood sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * GRW04/11 qPCR FAM Ct_Run2: qPCR CT score of bird blood sample, second run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * Ave Ct: Average of FAM Ct_Run1 and FAM Ct_Run2. If value = "Undetermined" for one run, this value will be same as the run for which a CT score is present. If both runs are Undetermined, this value is 0, indicating sample is negative for Plasmodium DNA. - LogParasit+0.001: Logarithmic value (base 10) of value in Parasitemia column with 0.001 added prior to taking the log. Not used - LogParasit: Logarithmic value (base 10) of value in Parasitemia column. If Parasitemia value is "0", no value in this column. Not used - LogParasite+1: Logarithmic value (base 10) of value in Parasitemia column with 1 added prior to taking the log. Not used #### HAAM_SlideReadings.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection measurements in blood samples taken from experimentally-infected Hawaii Amakihi (*Chlorodrepanis virens*), which are originally described in [K.L. Paxton et al. 2023 *Journal of Heredity*](https://doi.org/10.1093/jhered/esad017) and [C.M. Seidl et al. 2023 International Journal of Parasitology](https://doi.org/10.1016/j.ijpara.2023.10.001).  Infection measured through visual counts of parasitized cells on Giemsa-stained blood smears using microscopy and counts of Plasmodium DNA in bird blood sample measured by qPCR. Rows are individual bird blood samples. ##### Column names and variables: * Band Number: ID for individual bird * Species: 4-letter code denoting bird species. All "HAAM" or Hawaii Amakihi (*Chlorodrepanis virens)* * DPI: Days post infection for the bird. If blank, this value is unknown for individual. * Sampling Date: Date blood sample collected * Status: Sample taken from wild bird (Wild) or from a bird experimentally infected in a laboratory (Lab). All Lab. * Site Code: Abbreviated dode for location where bird was captured and sampled. All "Lab" - Magnification: Magification of compound microscope used to examine stained blood smear - Num Parasite cells: number of parasite cells observed in blood smear - Cells Examined: number of red blood cells examined in blood smear - Parasitemia: number of parasite cells observed divided by number of red blood cells examined within blood smear - Pos_Neg: Denotes whether sample was positive (pos) or negative (neg) for Plasmodium DNA using qPCR. All "Pos" * Ave Ct: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs. * LogParasit+0.001: Logarithmic value (base 10) of value in Parasitemia column with 0.001 added prior to taking the log. Not used * LogParasit: Logarithmic value (base 10) of value in Parasitemia column. If Parasitemia value is "0", no value in this column. Not used * LogParasite+1: Logarithmic value (base 10) of value in Parasitemia column with 1 added prior to taking the log. Not used #### LitParasitemias2.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection measurements from blood samples and outcomes for experimentally-infected Hawaiian bird species. These data are summaries from the following published studies: [Van Riper et al. 1986](&lt; https://doi.org/10.2307/1942550&gt;) *[Ecological Monographs](&lt; https://doi.org/10.2307/1942550&gt;)*, [Atkinson et al. 1995](https://doi.org/10.1017/S003118200007582X) *[Parasitology](https://doi.org/10.1017/S003118200007582X)*, [Yorinks & Atkinson 2000](https://doi.org/10.1093/auk/117.3.731) *[The Auk](https://doi.org/10.1093/auk/117.3.731)*, [Atkinson et al. 2000](https://doi.org/10.7589/0090-3558-36.2.197) *[Journal of Wildlife Diseases](https://doi.org/10.7589/0090-3558-36.2.197)*, [Atkinson et al. 2001 *The Condor*](https://doi.org/10.1093/condor/103.2.209), [Atkinson et al. 2014](https://doi.org/10.1007/s10393-013-0899-2) *[EcoHealth](https://doi.org/10.1007/s10393-013-0899-2)*. Data are infection levels of a bird or cohort of birds starting day 1 through 65 after infection with avian malaria. Empty cells indicate no data. ##### Column names and variables: * ID: Identifier for the study. Composed of 4-letter code for birds species and description of the published study (e.g., authors and date) which generated these data * SpeciesDiff: Code which denotes differences in species data * SpeciesCode: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. * SciName: Genus and species of tested bird * Source: First author and date of published study which generated these data * DOI: Digital Object Identifier for the published study which generated these data * N: number of birds which provided data in columns DPI01-DPI065. * Outcome: Whether birds in this study "Survived" or "Died" from experimental infection * DPI01 through DPI65: Parasitemia (fraction of red blood cells infected with avian malaria) on the numbered day post infection. Measurements taken on various days between 1 and 65. "0" values are true zeros. If cell is blank, no data. #### Prevalence_HIpointcount_stations.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection and prevalence results from blood samples taken from wild-caught birds captured at locations where point counts for this study were conducted to estimate relative bird species abundance and community composition. Point counts occurred February - June 2020. Results reported in **Abundance_species_site_o2.csv.** Plasmodium DNA in bird blood samples measured by qPCR. Rows are individual bird blood samples. Empty cells indicate no data. ##### Column names and variables: * Band Number: ID for bird using United States Geological Survey metal band number  * SpeciesCode: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. * NativevExo: Classifies bird as "Native" or "Exotic" to Hawaii * Family : Scientific family of individual * SubFamily: Scientific subfamily of individual * Genus: Scientific genus of individual * Species: Scientific species of individual * SciName: Combination of Genus and Species for individual * Sample Date: Date blood sample collected * Site Code: Abbreviated (4-letter) code for location where bird was captured and sampled * Island: Island of Hawaii (1 value = "Hawaii") * DNA Extraction Date: Date of DNA extraction from blood sample * qPCR Date: Date of qPCR testing for extracted DNA * Infection Designation: Denotes whether sample was positive (pos) or negative (neg) for avian malaria GRW4 * Average Ct: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs.This is the average value of 2 qPCR runs. * UTM Y: Spatial coordinates for Site Code * UTM X: Spatial coordinates for Site Code #### NegativeBirdsPhyloSingleParaEdit.csv **Description:** Estimated parasitemia values for bird species with no avian malaria infection data. Parasitemia values are the average of estimates for the closest related species based on avian phylogeny in 2022.  These data are used to quantify the infectiousness of a bird species (rows) to mosquitoes. Cells with "X" present indicate no data. ##### Column names and variables: * Band.Number: ID for bird using United States Geological Survey metal band number. If bird was unbanded, a unique 1-9 character code assigned * SpeciesCode: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. * NativevExo: Classifies bird as "Native" or "Exotic" to Hawaii * Family : Scientific family of individual * SubFamily: Scientific subfamily of individual * Genus: Scientific genus of individual * Species: Scientific species of individual * SciName: Combination of Genus and Species for individual * Sample Date: Date blood sample collected * Site Code: Abbreviated (4-letter) code for location where bird was captured and sampled * Island: Island of Hawaii (1 value = "Hawaii") * Infection.Designation: Denotes whether sample was positive (pos) or negative (neg) for avian malaria GRW4. All in this file are "neg" * Bird.Ct: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs. This is the average value of 2 qPCR runs. All in this file are "0". * Inc_Temp: Constant temperature in Celcius that a mosquito feeding on this bird would be held in. Only value is 24. This value is used to estimate infectiousness of this bird species to mosquitoes based on experimental infection results from in **2020_UCSC_BF_mosquitoes_Elvis_AllPlates.csv, 2023_BFMosquito_Aug01Dataset_age.csv,** and **2023_BFMosquito_Mar01Dataset_age.csv.** * DPE: Days post exposure for mosquito, had it fed upon this bird. Only value is 10. This value is used to estimate infectiousness of this bird species to mosquitoes based on experimental infection results from in **2020_UCSC_BF_mosquitoes_Elvis_AllPlates.csv, 2023_BFMosquito_Aug01Dataset_age.csv,** and **2023_BFMosquito_Mar01Dataset_age.csv.** * Parasitemia: Fraction of red blood cells infected with avian malaria. These values are the average of parasitemia estimates for the closest related species based on avian phylogeny in 2022.  #### oahu.prevalence.analysis.file.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection results for blood samples taken from wild-caught birds on island of Oahu in Hawaii. Samples collected by Hawai‘i Vertebrate Introductions and Novel Ecosystems project from 2014-2017. Rows are individual bird blood samples. Empty cells indicate no value. Some of these data also in **C_E_J_Birds_Combined_02222021.csv** ##### Column names and variables: * Band:  ID for bird using United States Geological Survey metal band number. If bird was unbranded, "noband" used. * SampleDate: Date blood sample collected * Month: Numeric month (1-12) in which sample was collected * Year: 4-digit year in which sample was collected * Species: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. * Site: Abbreviated identifier for location where bird was captured and sampled * result: whether samples was "positive" or "negative" for Plasmodium DNA by qPCR * Ct: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs.This is the average value of 2 qPCR runs. * Age: Age of bird at time of blood sampling. "a" = adult, "j" = juvenile  * tmin: Minimum temperature in Celcius at time of sample collection * tmax: Maximum temperature in Celcius at time of sample collection * precip: Precipitation in mm at time of sample collection * result_0_1: Integer indicating whether samples was positive "1" or negative "0" for Plasmodium DNA by qPCR * day_of_year: sequential day of the year number starting with day 1 on January 1st. * elevation: elevation in meters where bird was captured and sample collected #### Lapointe2010TempOocystSporozData.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infections in *Culex quinquefasciatus *mosquitoes across temperature from [LaPointe et al. 2010 Journal of Parasitology](https://doi.org/10.1645/GE-2290.1). Rows are infection results in mosquitoes at a given temperature. Empty cells indicate no data. ##### Column names and variables: * Trial: Identifier for number of experimental trials that generated this data. Two trials (1, 2) * Temperature: Temperature in Celcius mosquitoes were held in after feeding on an infected bird. * OocystPerc: Precentage of mosquitoes with oocysts in their midgut * FracOocyst: Fraction of mosquitoes with oocysts in their midgut * O_Npos_N: Number of mosquitoes with oocysts in their midgut/number of mosquitoes tested * SporozPerc: Precentage of mosquitoes with sporozoites in their salivary glands * FracSporoz: Fraction of mosquitoes with sporozoites in their salivary glands * S_Npos_N: Number of mosquitoes with with sporozoites in their salivary glands/number of mosquitoes tested * N: Total number of mosquitoes tested #### Abundance_species_site_o2_latlong.csv **Description:** Density estimates for birds species at sites where unlimited-distance point counts were conducted in February to June 2020. Density estimated (birds/ha) using distance sampling in the [Distance package in R](https://doi.org/10.18637/jss.v089.i01). Estimates use a half-normal key function, a truncation distance of 95 m, and a species by site detection function. ##### Column names and variables: * SiteCode: Abbreviated (4-letter) identifier for location where bird was detected * Species: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation * Estimate: density estimate (birds/ha) for species * se: standard error * cv: coefficient of variation * lcl: lower confidence interval * ucl: upper confidence interval * df: degrees of freedom * x: Spatial coordinates for Site Code * y: Spatial coordinates for Site Code #### Malaria_prevalence_EEID.csv **Description:** Avian malaria (*Plasmodium relictum* GRW4) infection results for blood samples taken from wild-caught birds from multiple islands in Hawaii. Rows are are individual bird blood samples collected between 2018 and 2020 by authors. #N/A or "0" value indicated no data. Some of these data also in **C_E_J_Birds_Combined_02222021.csv** ##### Column names and variables: * Band Number: ID for bird using United States Geological Survey metal band number. If bird was unbanded, a unique 1-9 character code assigned. * Resample: Designation of whether birds were sampled more than once at different times over the course of the study (i.e., recaptured in subsequent sampling trips. N = Not resampled, only sampled once; 1 = First sample;  2 = Second sample; 3 = Third sample * Sp.code: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. Note, JAWE is now WAWE * Sp.name: English common name for bird species * Sp.stat: Classifies bird as "native" or "exotic" to Hawaii * Age.1: Age of bird, based on plumage characteristics. See [https://www.usgs.gov/data/hawaii-island-forest-bird-phenology-and-morphometrics-1994-2019](https://www.usgs.gov/data/hawaii-island-forest-bird-phenology-and-morphometrics-1994-2019) for description of codes. "0" value indicates data not taken. * Age.2: Age of bird, based on additional aging characteristic. Adult, SubAdult, Juvenile, Unknown * Age.3: Age of bird, based on additional aging characteristic. Adult, Juvenile, Unknown * Sex: Sex of bird. Male = "M"; Female = "F"; Unknown = "U" * Site Code: Abbreviated identifier for location where bird was captured and sampled * Island: Island of Hawaii from which sample collected (Hawaii, Kauai, Maui, Oahu, Molokai) * avg_month_rf_mm: Average monthly rainfall for that site in mm * avg_month_tmax: Average monthly maximum temperature for site in Celcius * avg_month_tmin: Average monthly minimum temperature for site in Celcius * Sample Date: Date sample was collected * qPCR Run 1: qPCR CT score of bird blood sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * qPCR Run 2: qPCR CT score of mosquito sample, first run; "Undetermined" indicates sample never crossed threshold; sample is negative for Plasmodium DNA * avg qPCR: Average of qPCR Run 1 and qPCR Run 2. If value = "Undetermined" for one run, this value will be same as the run for which a CT score is present. If both runs are Undetermined, this value is "Und", indicating sample is negative for Plasmodium DNA. * preval.1: Denotes whether avg qPCR value is considered "positive" or "negative" for Plasmodium DNA * preval.2: Denotes whether avg qPCR value is considered "negative", positive ("pos") or lightly positive ("pos(low)") for Plasmodium DNA. pos(low) samples have avg qPCR CT values &gt; 38 * preval.3: Denotes whether the sample comes from a bird believed to be in its acute ("accute", avg qPCR CT &lt; 29 ) or chronic ("chronic", 30 38). "negative" = birds is not likely infected with avian malaria and which contain no detectable Plasmodium DNA (avg qPCR CT = Undetermined) #### BirdMassNative.csv **Description:** Average mass of bird species found in Hawaii that were encountered in during unlimited-distance point counts conducted in February to June 2020. ##### Column names and variables: * SpeciesCode: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. * Mass: mass in grams #### Malaria_prev_forMap.csv **Description**: Avian malaria (*Plasmodium relictum* GRW4) infection results for blood samples taken from wild-caught birds from multiple islands in Hawaii. Rows are are individual bird blood samples collected between 2014 and 2020 by authors. Empty cells indicate no value. Same data as in **C_E_J_Birds_Combined_02222021.csv** but now with elevation. **Column names and variables:** * Band Number: ID for bird using United States Geological Survey metal band number. If bird was unbanded, a unique 1-9 character code assigned * Sp.Code: 4-letter code denoting bird species. See [https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf](https://www.birdpop.org/docs/misc/Alpha_codes_eng.pdf) for translation. Except "Canary" which represents domestic canary. JAWE is now WAWE. * Site Code: Abbreviated (4-letter) code for location where bird was captured and sampled * Island: Island of Hawaii where bird sampled. Values = Hawaii, Oahu, Maui, Kauai. * Elevation: Elevation above sea level in meters * UTM Y: Spatial coordinates for Site Code * UTM X: Spatial coordinates for Site Code * Sample Date: Date blood sample was taken * avg qPCR: Malaria DNA amount in bird measured by qPCR, in CTs. "0" indicates sample never crossed threshold, sample is negative for Plasmodium DNA. This is the average value of 2 qPCR runs.This is the average value of 2 qPCR runs. ### Code/software #### BFMosq_to_BirdInfectious_12_24_25_upload.R This file conducts the majority of analyses and generates the majority of the Figures used in the manuscript. ##### Language and Environment R Environment for Statistical Computing ###### *Version* R 4.4.1 ###### Dependencies * tidyverse * lme4 * ggthemes * emmeans * ggpubr * glmmTMB * ggh4x * RColorBrewer * car * brglm2 * viridis * sf * terra * ggforce * rnaturalearth * elevatr