Question

this graph shows the beginning-of-year population counts for wolves in yellowstone national park from 1996 to 2023. yellowstone national park wolf population (graph with x-axis year from 1996 to 2023, y-axis number of wolves from 25 to 175) in 2008, yellowstone national park was colder than average for most of the year, including a very cold january and december. the following year, 2009, the park had a very cold fall and an exceptionally cold december. complete the paragraph using information from the graph. the wolf population size dropdown during 2008, when temperatures were colder than average, and dropdown during 2009, when the fall and winter were exceptionally cold. extreme temperature was dropdown and a dropdown limiting factor for the wolf population.

Explanation:

Step1: Analyze 2008 wolf population

From the graph, in 2008, the wolf population (at start of year) is high, but comparing to 2007 (around 175) and 2009 (lower), in 2008, the population peak is there, but then in 2009, it drops. Wait, the graph: 2008 start of year (x=2008) has a peak, then 2009 (next year) the population drops. So in 2008 (the year), the population during 2008 (from start of 2008 to start of 2009) – the graph shows start of 2008 is ~175, start of 2009 is lower (around 120? Wait no, the x-axis is year (start of year). So 2008 start: ~175, 2009 start: ~120? Wait no, looking at the graph: 2005 is ~175, 2006 drops to ~120, 2007 rises to ~175, 2008 start: ~175, 2009 start: ~95? Wait maybe I misread. Wait the y-axis is number of wolves, x-axis year (start of year). So 2008: the point at 2008 is high, then 2009 is lower. So during 2008 (the year), the population (from start of 2008 to start of 2009) – the graph's 2008 point is a peak, then 2009 is lower. So in 2008, the population size (during the year) – maybe the question is about the population size change during 2008 (from start of 2008 to start of 2009). Wait the first blank: "The wolf population size [blank] during 2008, when temperatures were colder than average". So looking at the graph, start of 2008: ~175, start of 2009: ~95? Wait no, maybe the graph's 2008 is a peak, then 2009 drops. So during 2008 (the year), the population (from start of 2008 to start of 2009) – the graph shows that at start of 2008, it's high, then by start of 2009, it's lower. So the population size during 2008 (the year) – maybe "remained high" or "peaked" but then in 2009, it "decreased". Wait the first blank: options? Wait the problem has dropdowns, but since we need to infer. Let's think about population dynamics. Cold temperatures: if 2008 was cold, and 2009 was very cold fall/winter. So in 2008 (the year), the population size – maybe "peaked" or "was high", then in 2009, it "decreased". Then extreme temperature was a "density-independent" limiting factor (since temperature is abiotic, density-independent) and a "significant" limiting factor. Wait, let's recall: density-independent factors (like temperature, natural disasters) affect population regardless of density; density-dependent (like competition, predation) depend on density. So extreme temperature is density-independent. So the blanks: first blank: "peaked" or "remained stable" but no, 2008 start is high, 2009 start is lower. So during 2008 (the year), the population size (from start of 2008 to start of 2009) – the graph shows that at start of 2008, it's high, then by start of 2009, it's lower. So maybe "increased" no, wait 2007 start is ~175, 2008 start is ~175 (same?), no, 2007: maybe 2007 start is ~175, 2008 start is ~175, then 2009 start is lower. Wait maybe the first blank: "was high" or "peaked", second blank: "decreased" (since 2009 start is lower than 2008 start). Then extreme temperature was a "density-independent" and a "significant" limiting factor. So putting it together:

The wolf population size **peaked** (or "was high") during 2008, when temperatures were colder than average, and **decreased** during 2009, when the fall and winter were exceptionally cold. Extreme temperature was **density-independent** and a **significant** limiting factor for the wolf population.

Wait, let's confirm:

1. 2008: start of year (2008) has a high population (graph shows peak at 2008), so during 2008 (the year), the population size was high or peaked. Then 2009: start of year (2009) is lower than 2008, so population size decreased during 2009 (from start of 2008 to start of 2009, the population dropped).

2. Extreme temperature (cold) is a density-independent factor (abiotic, affects regardless of population density) and a significant limiting factor (since it caused the population to drop).

So the blanks:

First: "peaked" (or "was high") – but likely "peaked" or "remained high" but maybe "decreased"? No, wait 2008 start is high, 2009 start is lower, so during 2008 (the year), the population (from start of 2008 to start of 2009) – the graph shows that at start of 2008, it's high, then by start of 2009, it's lower. So the population size during 2008 (the year) – maybe "decreased" no, wait the start of 2008 is the population at the beginning of 2008, then during 2008, the population might have peaked then dropped, but the question is about the population size "during 2008" – maybe the answer is "remained high" or "peaked", then "decreased" in 2009.

Then extreme temperature: density-independent (because it's an abiotic factor, not related to population density) and a "significant" (or "major") limiting factor.

So putting it all together:

The wolf population size **peaked** during 2008, when temperatures were colder than average, and **decreased** during 2009, when the fall and winter were exceptionally cold. Extreme temperature was **density - independent** and a **significant** limiting factor for the wolf population.

Answer:

The wolf population size \boxed{peaked} during 2008, when temperatures were colder than average, and \boxed{decreased} during 2009, when the fall and winter were exceptionally cold. Extreme temperature was \boxed{density - independent} and a \boxed{significant} limiting factor for the wolf population.