# 11.8: Data Dive- Island Fox Populations

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## Overview

The Island Fox Conservation Working Group and Friends of the Island Fox nonprofit organization work hard to continually fund research and conservation projects to ensure the continued survival of the island fox. In addition, they also have educational outreach programs about the island fox as an endangered species to get public support. Every June the Island Fox Conservation Working Group meets to go over updates and plan for the future. In the 2019 meeting they discussed population trends across the six island fox subspecies and determine what those populations mean for the subspecies trajectory moving into the future. The results of this meeting can be seen in the graph and table below:

Table $$\PageIndex{a}$$: The 2019 designated statuses for the subspecies of island fox based on fox population and island size. Graph by Rachel Schleiger (CC-BY-NC) modified from data in 2019 Island Fox Status Update.

Island Island Size Fox Population Status
San Miguel Small 171 Concerned
San Nicolas Small 400 Improved
Santa Rosa Large 1862 Stable
Santa Cruz Large 2462 Stable
Santa Catalina Large 1571 Stable
San Clemento Small 778 Stable

## Questions

1. What is the independent (explanatory) variable and the dependent (response) variable?
2. What question(s) are the authors trying to answer with this graph and table?
3. Which subspecies of island fox do you think is the most stable? Why?
4. Which year(s) were bad (meaning population estimates were very low) for most of the island fox subspecies?
5. As noted in the graph, populations are estimated for each subspecies annually. Why do you think an annual estimation was chosen in the conservation plan instead of a longer time interval?

## Raw Data From Above Graph(s)

Table $$\PageIndex{b}$$: Raw data for population trends for subspecies of island fox (solid lines = large island subspecies, dashed lines = small island subspecies). Graph by Rachel Schleiger (CC-BY-NC) modified from data in 2019 Island Fox Status Update.

Year San Clemento San Nicolas San Miguel Santa Rosa Santa Cruz Santa Catalina
1994 1000 520 450 1800 1500 1300
1996 810 550 100 400 1100 800
1998 650 550 40 100 800 300
2000 800 450 20 50 100 200
2002 450 500 25 60 90 350
2004 450 500 50 70 200 375
2006 400 506 100 80 300 650
2008 400 725 260 100 750 900
2010 900 500 500 350 1050 1000
2012 850 640 525 700 1800 1500
2014 1200 263 510 900 2750 1750
2016 860 329 329 1600 2400 1400
2017 775 255 255 1800 3150 2050
2018 790 400 200 1800 2500 1600