scavenger_community {ecoteach}R Documentation

Scavenger community structure in Scandinavian ecosystems

Description

This dataset contains observations of scavenger communities along an environmental gradient from boreal forest to alpine tundra in central Scandinavia. The data was collected using baited camera traps to quantify the structure of the winter scavenger community and assess how climatic conditions affected spatial patterns of species occurrences at baits. The study found that habitat type (forest or alpine tundra) and snow depth were main determinants of community structure. Occurrence at baits by habitat generalists (red fox, golden eagle, and common raven) typically increased at low temperatures and high snow depth, likely due to increased energetic demands and lower abundance of natural prey in harsh winter conditions.

Usage

scavenger_community

Format

A data frame with 1255 rows and 61 variables:

id

Site identifier (factor)

year

Year of observation (numeric)

jd

Julian day (numeric)

photo_sum

Total number of photos (numeric)

empty

Number of empty photos (numeric)

raven

Number of photos with ravens (numeric)

crow

Number of photos with crows (numeric)

magpie

Number of photos with magpies (numeric)

eurjay

Number of photos with Eurasian jays (numeric)

sibjay

Number of photos with Siberian jays (numeric)

geagle

Number of photos with golden eagles (numeric)

wteagle

Number of photos with white-tailed eagles (numeric)

rlbuzz

Number of photos with rough-legged buzzards (numeric)

goshawk

Number of photos with goshawks (numeric)

redfox

Number of photos with red foxes (numeric)

arcfox

Number of photos with arctic foxes (numeric)

wolverine

Number of photos with wolverines (numeric)

badger

Number of photos with badgers (numeric)

pinemart

Number of photos with pine martens (numeric)

mustelids

Number of photos with other mustelids (numeric)

lb

Total number of photos with large birds (numeric)

bird

Total number of photos with birds (numeric)

mammal

Total number of photos with mammals (numeric)

age

Age of bait in days (numeric)

snow

Snow presence indicator (numeric)

session

Sampling session identifier (factor)

ravenm

Raven presence/absence (numeric)

crowm

Crow presence/absence (numeric)

magpiem

Magpie presence/absence (numeric)

eurjaym

Eurasian jay presence/absence (numeric)

sibjaym

Siberian jay presence/absence (numeric)

geaglem

Golden eagle presence/absence (numeric)

wteaglem

White-tailed eagle presence/absence (numeric)

rlbuzzm

Rough-legged buzzard presence/absence (numeric)

goshawkm

Goshawk presence/absence (numeric)

redfoxm

Red fox presence/absence (numeric)

arcfoxm

Arctic fox presence/absence (numeric)

wolverinem

Wolverine presence/absence (numeric)

badgerm

Badger presence/absence (numeric)

pinemartm

Pine marten presence/absence (numeric)

mustelidsm

Other mustelids presence/absence (numeric)

arcfox.day

Arctic fox detected that day (numeric)

redfox.day

Red fox detected that day (numeric)

wolverine.day

Wolverine detected that day (numeric)

raven.day

Raven detected that day (numeric)

crow.day

Crow detected that day (numeric)

magpie.day

Magpie detected that day (numeric)

geagle.day

Golden eagle detected that day (numeric)

wteagle.day

White-tailed eagle detected that day (numeric)

badger.day

Badger detected that day (numeric)

pinemart.day

Pine marten detected that day (numeric)

eurjay.day

Eurasian jay detected that day (numeric)

sibjay.day

Siberian jay detected that day (numeric)

lb.day

Large bird detected that day (numeric)

se

Session identifier (numeric)

bird.day

Any bird detected that day (numeric)

mammal.day

Any mammal detected that day (numeric)

length

Length of session (numeric)

samean

Mean solar angle (numeric)

tamean

Mean temperature (numeric)

habitat

Habitat type: "Boreal forest" or "Alpine tundra" (factor)

hosl

Hours of sunlight (numeric)

scover

Snow cover: "Snow cover" or "No snow cover" (factor)

loghosl

Log-transformed hours of sunlight (numeric)

altitude

Altitude in meters (numeric)

sdepth

Snow depth in cm (numeric)

Source

Gomo, Gjermund and Rød-Eriksen, Lars and Andreassen, Harry P. and Mattisson, Jenny and Odden, Morten and Devineau, Olivier and Eide, Nina E. (2020). Scavenger community structure along an environmental gradient from boreal forest to alpine tundra in Scandinavia. Ecology and Evolution. doi:10.1002/ece3.6834

Examples


# Load the dataset
data(scavenger_community)

# Basic exploration
head(scavenger_community)
summary(scavenger_community)

# Species richness by habitat type
if(require(dplyr)) {
  # Count number of unique species by examining columns with species data
  scavenger_community %>%
    group_by(habitat) %>%
    summarize(
      raven_present = sum(ravenm > 0, na.rm = TRUE),
      redfox_present = sum(redfoxm > 0, na.rm = TRUE),
      wolverine_present = sum(wolverinem > 0, na.rm = TRUE),
      total_species = raven_present + redfox_present + wolverine_present
    )
}

# Compare bird vs mammal occurrence between habitats
if(require(dplyr)) {
  scavenger_community %>%
    group_by(habitat) %>%
    summarize(
      bird_observations = sum(bird, na.rm = TRUE),
      mammal_observations = sum(mammal, na.rm = TRUE),
      observation_ratio = bird_observations / mammal_observations
    )
}

# Visualize snow depth distribution by habitat
if(require(ggplot2)) {
  ggplot(scavenger_community, aes(x = sdepth, fill = habitat)) +
    geom_histogram(position = "dodge", bins = 20) +
    labs(title = "Snow depth by habitat type",
         x = "Snow depth (cm)",
         y = "Count")
}


[Package ecoteach version 0.1.0 Index]